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Nuisance-call blocker fined £190k for being a nuisance caller

UK regulators fined Elderly Aids £190,000 after the firm made 758,000 unwanted calls yearly selling call-blocking devices.

Elderly Aids, a company selling devices to block unwanted calls, was fined £190,000 for making around 758,000 nuisance calls per year. The enforcement action highlights ongoing regulatory scrutiny of telemarketing practices. No cyber incident or data exposure was involved.

The Register · Security · 20d agoPolicy & legal

FCC proposes public scorecard to rate telecoms on anti-robocall efforts

The FCC proposed a public scorecard rating telecoms' anti-robocall effectiveness and removed 14 providers from US networks for compliance failures.

The Federal Communications Commission issued a public notice proposing a scorecard that would assess how effectively retail voice providers, including wireless, wireline and VoIP, prevent illegal robocalls, drawing on Robocall Mitigation Database filings, consumer complaint and enforcement data. The agency stressed it is not a rulemaking imposing new requirements, and it is seeking comment on scope, such as whether to focus on larger providers. The same day, the FCC removed 14 providers from the Robocall Mitigation Database for non-compliance, effectively requiring other US providers to block their traffic within two days.

CyberScoop · 14d agoPolicy & legal

Researchers Build WeChat Zero-Click Worm Hijacking Phones via Calls

Calif researchers built WeWorm, a zero-click worm exploiting a WeChat VoIP memory-corruption RCE that Tencent has now patched.

Calif researchers found a memory corruption flaw in WeChat's VoIP stack in July using LLM-assisted analysis and built working exploits within two days, then integrated them into WeWorm, which they call the first zero-click worm spreading through WeChat calls on iOS and Android. A crafted incoming call yields remote code execution with no user interaction, giving full control of the victim's WeChat account; the attacker only needs to be on the victim's friend list, easily achieved by compromising a contact first. Tencent confirmed the bug and shipped patches in WeChat Android 8.0.77 and iOS 8.0.76, and chaining with other OS bugs could yield full device control.

Infosecurity Magazine · 7d agoExploit / PoC

Getting a stranger’s phone kicked off the cellular network costs a few dollars

Researchers show attackers can remotely block strangers' phones and alarm gateways on US cellular networks by abusing lost/stolen IMEI reporting for $2.50-$4 per device.

Researchers from Michigan State University and three partner schools found six weaknesses in the lost/stolen device reporting ecosystem spanning devices, carrier systems, and cross-carrier block-list sharing. They demonstrated blocking unopened Samsung Galaxy Z Fold 7 phones and home alarm gateways on three major US carriers, with each block costing $2.50-$4 and taking roughly 20-80 seconds. The attacks exploit thin identity and ownership checks in prepaid accounts, IMEI leakage from vulnerable cellular chipsets used by two vendors with over 40% global market share, and pre-release IMEI databases purchasable for $600. Victims receive no notification, and restoring service requires proving device ownership to the carrier.

Help Net Security · 5d agoResearch

Product showcase: ScamNet looks for warning signs in suspicious calls and shady links

Synaptrex's ScamNet app filters scam calls, messages and websites on Apple devices using on-device AI and reputation checks.

ScamNet: Anti-Scam Suite from Synaptrex Technologies is a free consumer app (with ScamNet+ subscription) for iPhone, iPad and Mac that blocks robocalls and spam via iOS Call Blocking & Identification, filters unknown senders with an offline detection engine, and provides a Safari extension that analyzes and blocks suspicious websites. A Check/Report tool accepts phone numbers, websites, crypto addresses, text, images and audio, and a Device Shield verifies passcode, OS updates and screen-recording status.

Help Net Security · Aug 17, 2026Tools

WeChat Zero-Click Worm Took Over Accounts on iPhone and Android via Incoming Calls

Researchers demonstrated a zero-click WeChat worm that hijacked accounts via incoming calls; Tencent blocked the exploit server-side after July disclosure, no real attacks reported.

Security firm Calif built a worm that seized WeChat accounts via incoming calls without any target interaction, demonstrating it spreading across three test phones (Android to iPhone to Android). Once exploited, the attacker gains full control of the WeChat account, including messages, calls, payments, and mini programs, though not the phone itself. Tencent mitigated the flaw server-side, confirmed blocked on 28 August, shipping WeChat 8.0.77 for Android and 8.0.76 for iOS on 21 August. No CVE has been assigned, Tencent published no advisory, and no attacks in the wild have been reported; WeChat/Weixin counts 1.439 billion monthly active users.

The Hacker News · 8d agoVulnerability1

WeWorm – First 0-Click Worm Spreading Through WeChat Calls Across iOS and Android

Researchers demonstrated WeWorm, a zero-click worm exploiting a memory-corruption flaw in WeChat's VoIP stack to spread via calls across iOS and Android.

Security firm Calif published WeWorm, a proof-of-concept zero-click worm exploiting a memory-corruption bug in WeChat's VoIP stack to spread through voice calls on iOS and Android without the victim answering. The demo chained a Pixel 10a, an iPhone 17e, and a second Pixel 10a, compromising each device while the call was still ringing and giving full control of the WeChat account. The attacker must already be on the victim's friend list, but compromised contacts become the propagation layer across a platform with over 1.4 billion monthly users. Calif reported the bug to Tencent in July 2026, and Tencent has since mitigated it; full technical details are withheld for a later conference presentation.

Cyber Security News · 8d agoExploit / PoC

WeChat Worm Can Hijack Accounts Without Victims Answering Calls

Researchers demoed WeWorm, a zero-click WeChat worm hijacking accounts via incoming VoIP calls using a memory corruption flaw; Tencent patched it in August.

Researchers at Calif exploited a memory corruption bug in WeChat's VoIP system, taking over accounts through an incoming call even if the victim never answers or touches the phone. The attacker must already be a WeChat contact, but compromising a friend's account bypasses this, and chained calls spread the worm across three Android and iOS test phones in seconds. Tencent fixed the flaw in Android 8.0.77 and iOS 8.0.76 released in August, and researchers found no evidence of real-world exploitation. WeChat and Weixin reported 1.418 billion combined monthly active users at the end of 2025.

Security Affairs · 7d agoExploit / PoC

WeChat worm could pwn a friend before they even answered the call

Calif researchers demoed WeWorm, a zero-click WeChat VoIP memory-corruption worm enabling account takeover; Tencent patched it August 21.

Security firm Calif found a memory corruption bug in WeChat's VoIP stack that let a trusted contact take over a user's account simply by calling them, without the call being answered. The demo worm then called the victim's contacts to self-propagate across iOS and Android; declining the call prevented infection. Tencent pushed fixes on August 21, and Calif said chaining the bug with other Android and iOS flaws could yield full device control. Calif used AI to find the vulnerability and build its first RCE exploit in about two days.

The Register · Security · 7d agoExploit / PoC

Cisco Desk Phone 9800 Series, IP Phone 7800 and 8800 Series, and Video Phone 8875 with SIP Software Denial of Service Vulnerability

Cisco warns of a DoS flaw in SIP software on Desk Phone 9800 and IP Phone 7800/8800 series from improper HTTP packet memory handling.

Cisco disclosed a denial of service vulnerability affecting Desk Phone 9800 Series, IP Phone 7800 and 8800 Series, and Video Phone 8875 devices running Cisco SIP Software. An unauthenticated remote attacker can send a continuous stream of crafted HTTP packets, causing sustained memory consumption until the device becomes unresponsive. A manual reboot is required to recover an affected device. No CVE identifier was listed in the advisory text.

Cisco Security Advisories · 14d agoAdvisory

UNISOC Modem Flaw Enables Remote Code Execution via Video Calls

A UNISOC modem flaw allows attackers to achieve kernel-level remote code execution through malicious video calls on affected devices.

UNISOC, whose modems are widely deployed in Android smartphones, has a flaw that enables kernel-level code execution triggered via video calls. Successful exploitation would give an attacker deep control over affected handsets. No exploitation activity is mentioned in the report.

Infosecurity Magazine · Aug 17, 2026Vulnerability

“Zero-click” WeChat worm could hijack accounts and spread via a single call

Researchers discovered a critical memory corruption flaw in WeChat's VoIP stack enabling a zero-click worm, WeWorm, that hijacks accounts via calls; Tencent patched it.

Calif researchers weaponized a memory corruption issue in WeChat's VoIP stack into "WeWorm", a worm that spreads through WeChat calls without user interaction, hijacks each victim's account, and propagates via saved contacts across iOS and Android, potentially reaching millions of devices within hours. Exploitation takes seconds and grants full account control, and chaining with other reported Android/iOS bugs could lead to full device control. Tencent issued updated WeChat versions for iOS and Android and applied server-side mitigations; technical details remain withheld. WeChat has over a billion users, overwhelmingly in China.

Help Net Security · 8d agoVulnerability

Wireshark 4.6.8 patches 28 security bugs, nine in file parsers

Wireshark 4.6.8 fixes 28 security bugs, including nine crash-prone capture file parsers, misdecoded 5G fields, and memory-safety issues.

Wireshark 4.6.8 fixes 28 security bugs spanning advisories wnpa-sec-2026-64 through wnpa-sec-2026-91, including nine crash bugs in file parsers such as pcapng, Endace ERF and Tektronix K12xx that trigger when opening capture files. Fixes cover dissectors for RDP, SSH, Kerberos, H.245, CMS, C12.22 and several Bluetooth protocols, plus unnumbered memory-safety issues like a stack buffer overflow in the K12/RF5 writer. The release also corrects eight misdecoded 5G NAS/5GSM fields and moves the Unix extcap path to /usr/libexec/wireshark/extcap.

Help Net Security · Aug 13, 2026Advisory

SpecGuard: Inference-Time Backdoor Detection For Free

SpecGuard detects backdoored LLM behavior at inference time using speculative decoding acceptance rates, adding no extra model computation.

Researchers propose SpecGuard, an inference-time backdoor detector that repurposes draft-token acceptance rates from speculative decoding as a detection signal at zero added model-computation cost. When a trigger shifts the target model toward attacker-controlled behavior, the clean draft model's acceptance rate changes, exposing the backdoor; the paper formalizes when this signal appears and shows suppressing it weakens the backdoor. Experiments across diverse backdoor types and model families show reliable detection, including stealthy cases invisible to input-level filters. Speculative decoding is positioned as a free, always-on monitor for frequently updated deployed models.

arXiv cs.CR · 6d agoAI safety & security 2 sources2

Unisoc VoLTE Video Call Exploit Chain Can Give Attackers Full Android Kernel Access

Unisoc modem firmware flaw CWE-1189 allows VoLTE video call RCE chain to gain full Android kernel access on T606/T612/T7250 chipsets; no patch yet.

SSD Secure Disclosure published the second stage of an exploit chain, first disclosed in March 2026, that achieves full Android kernel access on Unisoc modem firmware via a VoLTE video call. The privilege-escalation flaw, classified as CWE-1189 (Improper Isolation of Shared Resources on System-on-a-Chip), exploits shared physical memory between modem and application processor with no hardware boundary, letting modem code map the entire 32-bit address space and modify Android kernel pages via ARM Memory Protection Unit registers. Confirmed affected chipsets include Unisoc T606 (Motorola E13), T612 (Realme C33), and T7250 (Xiaomi Redmi A5), sold across more than 140 countries. No CVE has been assigned, the August 2026 Android Security Bulletin does not address it, and Unisoc has not responded to researchers; exploitation requires an attacker-controlled private 4G network and a victim answering the call.

ZDI-26-609: Linux Kernel Net Scheduler Packet Classifier Use-After-Free Local Privilege Escalation Vulnerability

The Linux kernel net scheduler packet classifier has a use-after-free (CVSS 7.8) allowing local attackers to escalate privileges from low-privileged code.

ZDI-26-609 describes a use-after-free vulnerability in the Linux kernel's network scheduler packet classifier, with a CVSS score of 7.8. An attacker must first be able to execute low-privileged code on the target system before escalating privileges. The advisory text does not list an assigned CVE identifier.

ZDI Published Advisories · 23d agoVulnerability

ZDI-26-656: PAPPL Job Processing Heap-based Buffer Overflow Remote Code Execution Vulnerability

ZDI-26-656: Unauthenticated heap-based buffer overflow in PAPPL job processing allows remote code execution, rated CVSS 9.8.

The Zero Day Initiative published advisory ZDI-26-656 for PAPPL, the open-source printer application framework. A heap-based buffer overflow in job processing allows remote attackers to execute arbitrary code with no authentication required. ZDI assigned a CVSS 9.8 rating. No CVE identifier was listed in the advisory text.

ZDI Published Advisories · 6d agoAdvisory 2 sources

A Malicious SIM Card Can Run Attacker Code Inside the Modems Behind Cellular IoT Devices

Researchers showed malicious SIM cards can issue RUN AT commands to execute code on Qualcomm modems, compromising Quectel-based cellular IoT devices like EV chargers.

Researchers at the University of Birmingham and Fuzzware found 9 of 26 tested devices accept SIM proactive commands, including six Qualcomm-based cellular modules, five of them Quectel. They achieved code execution on a commercial Autel EV charger via the Quectel EC25's atfwd_daemon unsafe format string, and demonstrated an irreversible 2G downgrade, modem power-off, and arbitrary file reads via a root TFTP daemon on a Quectel EG25-G. Attacks require a hostile SIM already in the slot or an interposer; no attacks have been reported in the wild. Qualcomm has built a hardened configuration disabling the interface by default and Quectel mitigated the file-access flaw; the paper was presented at USENIX WOOT.

The Hacker News · Aug 11, 2026VulnerabilityCVE-2025-48618

Evaluating Practical Enumeration and Blocking Attacks on the Snowflake Circumvention System

Ethical measurements enumerated 21,000+ Snowflake proxy IPs across ~1,000 ASes; blocking top 1% of ASes disrupts 30% of Snowflakes.

Researchers tested Snowflake's assumptions that proxy IPs cannot be easily enumerated and that blocking them causes unacceptable collateral damage. Over 48 days of real-world measurements (May-June 2025), malicious-client-style enumeration collected over 21,000 unique proxy IPs across almost 1,000 autonomous systems. Blocking the top 1% of ASes blocks more than 30% of observed Snowflakes while affecting about 2.5% of Tranco Top 1M domains, and the broker's load-aware matching leaks stable high-capacity proxies to attackers. Some proposed mitigations have already been integrated into Snowflake.

arXiv cs.CR · 5d agoResearch1

Understanding the Security Boundary of Obfuscation-based On-Device LLM Protection

Researchers formalize obfuscation primitives for TEE-protected on-device LLMs and show a Collapse attack breaks ArrowCloak, TSQP, and LoRO, then extend the boundary.

The paper formalizes obfuscation primitives for TEE-Shielded LLM Partition (TSLP) schemes that offload computationally intensive layers from a Trusted Execution Environment to external GPUs. A novel primitive-guided attack, Collapse, demonstrates a shared vulnerability in prominent published methods including ArrowCloak (Security'25), TSQP (S&P'25), and LoRO (NeurIPS'25). The authors then introduce two new obfuscation primitives and integrate them with existing constructs to formulate an extended security boundary (O_ext).

arXiv cs.CR · 7d agoAI safety & security

From Specs to Apps: Verifying and Monitoring Models of Signal and WhatsApp

Researchers use the SpecMon runtime monitor to verify WhatsApp Web and Signal Desktop against formal Signal protocol models, finding undocumented libsignal fork differences.

The paper applies SpecMon, a runtime monitoring tool, to check whether executions of WhatsApp Web and Signal Desktop conform to formal models of the Signal protocol. The authors instrument both applications and build Tamarin-compatible multiset-rewrite models, including the first model of WhatsApp Web's implementation and the most detailed model to date of Signal's original protocol. They verify authentication and secrecy properties for core Signal protocol components, show monitoring detects deliberately injected faults with low overhead, and identify previously undocumented behavioral differences between the original libsignal library and WhatsApp's fork.

arXiv cs.CR · 6d agoResearch

ZDI-26-589: BlueZ A2DP Stack-based Buffer Overflow Remote Code Execution Vulnerability

ZDI details a network-adjacent stack buffer overflow in BlueZ's A2DP stack (CVE-2026-19774, CVSS 7.1) allowing remote code execution after pairing a malicious Bluetooth device.

The Zero Day Initiative published advisory ZDI-26-589 for a stack-based buffer overflow in BlueZ, the Linux Bluetooth protocol stack. A network-adjacent attacker who can pair a malicious Bluetooth device with the target can execute arbitrary code on the affected installation. The flaw carries a CVSS 7.1 rating and is tracked as CVE-2026-19774.

ZDI-26-571: Linux Kernel Net Scheduler Packet Classifier API Use-After-Free Local Privilege Escalation Vulnerability

ZDI disclosed a use-after-free local privilege escalation flaw (CVE-2026-64530) in the Linux Kernel net scheduler packet classifier API.

The Zero Day Initiative published ZDI-26-571 describing a use-after-free in the Linux Kernel net scheduler packet classifier API. Local attackers who can already execute low-privileged code can escalate privileges. ZDI assigned a CVSS score of 8.8 and the identifier CVE-2026-64530.

ZDI Published Advisories · Aug 13, 2026VulnerabilityCVE-2026-645301

Pixel Modem Zero-Day Exploited in Targeted Attacks

Google patched Pixel modem zero-day CVE-2026-58704, a zero-click permission bypass enabling remote privilege escalation, exploited in targeted attacks.

CVE-2026-58704 is a high-severity logic error in the Pixel cellular modem allowing remote (proximal/adjacent) escalation of privilege with no user interaction or additional execution privileges. Google reports limited, targeted exploitation but has not attributed it; the zero-click modem nature suggests commercial spyware or state-sponsored actors. The September Pixel update also fixes more than 100 other Pixel-specific vulnerabilities, nearly 50 of them critical, enabling RCE or privilege escalation.

SecurityWeekupdated · 3h agofirst · 4h agoExploit / PoC in the wild 7 sourcesCVE-2026-58704

New ‘ShieldCrash’ Zero-Day Exploit Targets Microsoft Defender

Researcher Nightmare Eclipse released ShieldCrash, a Microsoft Defender zero-day PoC bypassing ShieldBreak patches to gain System privileges on Windows.

The researcher known as Nightmare Eclipse released a PoC zero-day exploit dubbed ShieldCrash against Microsoft Defender on fully patched Windows systems. The exploit grants arbitrary file read with System privileges and can be used to drop the SAM database. It bypasses Microsoft's September 3 fixes for ShieldBreak (CVE-2026-69414), which itself bypassed patches for the RoguePlanet race condition (CVE-2026-50656). Microsoft has been contacted for comment and has not yet responded.

SecurityWeekupdated · 6d agofirst · 6d agoExploit / PoC 3 sourcesCVE-2026-50656CVE-2026-694141

Manic: The Android Malware That Exfiltrates Data Even When the Phone Is Offline

ThreatFabric identifies Manic, an Android banking fraud and spyware platform targeting Ukraine with offline Bluetooth/Wi-Fi Direct mesh exfiltration and device takeover.

ThreatFabric's Mobile Threat Intelligence team identified Manic, an Android malware active in the wild since at least February 2026 that combines banking fraud with surveillance and device-control capabilities. It monitors 169 Android apps including Ukrainian banks, government and eID services, messaging apps, crypto exchanges, and 2FA tools, using the Accessibility service as a classified UI keylogger and WebRTC for live screen viewing and remote control. A distinctive store-and-forward relay exfiltrates AES-GCM-encrypted data through nearby infected devices over Wi-Fi Direct, Bluetooth RFCOMM, or BLE GATT, supporting chains of up to four hops when direct C2 is unavailable. A July update added stronger anti-analysis, in-memory DEX loading, lock-secret phishing to extract device PINs, and hiding from the app launcher.

Security Affairs · 27d agoMalware in the wild

PaperCut Zero-Day Exploited in Attacks, Affecting All NG and MF Versions

PaperCut warns of actively exploited zero-day RCE chain CVE-2026-81578 and CVE-2026-82078 affecting all PaperCut NG and MF versions.

PaperCut alerted customers that attackers are actively exploiting a zero-day affecting all versions of PaperCut NG and MF print management software, with confirmed customer incidents and an ongoing investigation. Emergency patches were released for v25 and v26, and the flaw was later identified as an exploitation chain of CVE-2026-81578 and CVE-2026-82078 enabling remote code execution. Shared IoCs include suspicious post-exploitation activity from pc-app.exe and missing, truncated or deleted server.log files with specific database errors. Users with internet-exposed PaperCut Application Servers are urged to immediately restrict access to trusted IPs; in 2023, CVE-2023-27350 (CVSS 9.8) in the same products was exploited by Lace Tempest to deliver Cl0p and LockBit ransomware.

Researcher Drops New Microsoft Defender PoC Showing ShieldBreak Patch Can Be Bypassed

Researcher Chaotic Eclipse released a PoC showing CVE-2026-69414's patch is bypassable, allowing arbitrary file reads as SYSTEM on current Windows.

The researcher known as Chaotic Eclipse published a proof-of-concept for a zero-day in Microsoft Defender, dubbed ShieldCrash, assessed as a patch bypass for ShieldBreak (CVE-2026-69414, CVSS 7.8). The PoC demonstrates an arbitrary file read as SYSTEM with the latest Windows installed, and all supported desktop versions are said to be impacted. Microsoft patched the original issue in Microsoft Malware Protection Engine 1.1.26080.3, which updates automatically. The same researcher recently released PoCs for flaws in CrowdStrike Falcon Sensor, Kaspersky, Avast Antivirus and NVIDIA.

The Hacker News · 7d agoExploit / PoCCVE-2026-694141

Quoting Calif Research

Calif Research demos WeWorm, an AI-built zero-click worm that spreads via WeChat calls on iOS and Android without user interaction.

Calif Research released a demo of WeWorm, described as the first zero-click worm to spread through WeChat calls across iOS and Android; victims need not answer the call and hear nothing even if they do. The team used AI to find the underlying bug and write a remote code execution exploit in about two days, then spent one more week building the worm. The researchers argue AI can now do most of the exploit-development work, with humans supplying judgment on targeting and safe testing.

Simon Willison · 6d agoAI safety & security