Threat Brief: OWASSRF Vulnerability Exploitation
Unit 42 details active exploitation of Exchange SSRF flaws CVE-2022-41080/CVE-2022-41082 via the OWASSRF method, deploying the SilverArrow PowerShell backdoor.
Unit 42 documents OWASSRF, an exploit chain combining CVE-2022-41080 and CVE-2022-41082 to achieve remote code execution on Microsoft Exchange via Outlook Web Access, bypassing Microsoft's ProxyNotShell mitigations. Active exploitation was observed in late November and early December 2022, affecting at least eight organizations. Attackers authenticated to Exchange, then executed a PowerShell backdoor tracked as SilverArrow to create admin accounts, install AnyDesk, tunnel RDP via PuTTY Link, and dump LSASS memory for credential theft. Exploitation is isolated rather than mass-scale because authentication is required.
SharePoint RCE CVE-2026-45659 Added to CISA KEV After Active Exploitation
CISA adds actively exploited SharePoint RCE CVE-2026-45659 (CVSS 8.8) to KEV; an August 11 update confirms ransomware groups are exploiting the flaw.
CVE-2026-45659 is a deserialization of untrusted data RCE in Microsoft SharePoint Server affecting Subscription Edition, 2019, and 2016, patched by Microsoft in May 2026. An authenticated attacker with at least Site Member permissions can execute code remotely over the network. CISA added the flaw to its KEV catalog on July 2 with a July 4 deadline for federal agencies, and on August 11 confirmed ransomware groups are exploiting it. Microsoft separately described Storm-2603 (Warlock ransomware) and an unrelated actor co-existing in one network, with initial access likely via the Gladinet Triofox flaw CVE-2025-11371 (CVSS 9.1).
PaperCut Zero-Day Under Active Attack: Emergency Patch Released
PaperCut warns that a zero-day in NG and MF print management products is being actively exploited, shipping emergency patches with no CVE assigned yet.
PaperCut Software confirmed active exploitation of a zero-day affecting PaperCut NG and MF, with confirmed customer incidents, and released emergency patches on Friday ahead of technical details or a CVE assignment. The company urges customers to restrict web access to trusted IP addresses, disconnect application servers from the internet, and watch for indicators including tampered or truncated server.log files, database error strings, and suspicious activity involving pc-app.exe. The article recalls the May 2023 exploitation of CVE-2023-27350 and CVE-2023-27351 by the financially motivated Lace Tempest group, a Clop ransomware RaaS affiliate, though no attacker attribution has been given for the current campaign.
Microsoft discloses two actively exploited zero-days among 974 vulnerabilities
Microsoft patches 974 flaws in record Patch Tuesday, including two actively exploited Windows zero-days enabling privilege escalation.
Microsoft's largest-ever Patch Tuesday addresses 974 vulnerabilities, with CVE-2026-81963 (Windows Update Stack) and CVE-2026-85880 (Windows Advanced Local Procedure Call) exploited before disclosure. Both zero-days carry CVSS 7.8 ratings and allow privilege escalation. More than 10% of the defects are rated critical, and researchers attribute the record volume to AI-assisted vulnerability discovery without a matching rise in active exploitation.
Rogue ScreenConnect Installations Across Unrelated Hosts Suggest Worm-Like Activity
Huntress observed rogue ScreenConnect deployments with worm-like VBScript propagation across unrelated organizations, prompting a ConnectWise advisory on file transfer behavior.
Huntress identified multiple incidents in late August 2026 where social engineering led to rogue ScreenConnect remote access clients deployed on victim machines, which then spawned wscript.exe to run four VBScript payloads (1.vbs through 4.vbs) for profiling, telemetry collection, and persistence via a WindowsServiceHost Run key. Modified ScreenConnect clients propagated the VBScript chain to connected endpoints, creating worm-like spread. ConnectWise published an advisory on September 3, 2026, confirming an issue affecting file transfer behavior in both cloud and on-premises ScreenConnect deployments, with a CVE and fix expected within the week; partners were advised to review and disable TransferFiles permissions in the interim.
Poland's CERT Warns of Active Exploitation of Critical Zimbra Collaboration Suite Flaw
CERT Polska confirms active exploitation of critical unauthenticated RCE CVE-2026-73570 in Zimbra Collaboration Suite, patched July 20.
CERT Polska confirmed threat actors are actively exploiting CVE-2026-73570, an unauthenticated OS command injection in Zimbra Collaboration Suite allowing arbitrary shell commands as the zimbra user. Exploitation requires the SNMP trap service via snmp_notify with swatchdog running, which is enabled by default; Shadowserver tracks over 12,100 internet-exposed Zimbra servers. Zimbra fixed the flaw in version 10.1.20 on July 20, 2026, 28 days before exploitation was confirmed. Historical Zimbra targeting includes Winter Vivern, APT29, and APT28 campaigns.
Active Exploitation Attempts Target WSO2 API Manager JWT Bypass With Forged Admin Tokens
watchTowr observed active exploitation of CVE-2026-5430, a WSO2 API Manager JWT bypass using forged admin tokens, risking credential theft and account takeover.
CVE-2026-5430 (CVSS 9.8-10.0), an improper cryptographic signature verification flaw in WSO2 API Manager, lets JWT authentication be bypassed with unsupported algorithms, enabling administrative account takeover. watchTowr honeypots captured forged JWT tokens with baked-in administrator privileges on September 13, 2026, which could expose API credentials, consumer keys, and secrets for every registered application. Affected products include WSO2 API Manager 4.1.0-4.6.0, API Control Plane, Traffic Manager, and Universal Gateway. Fixes are available via GitHub pull requests and subscription update levels, and users are urged to patch immediately.
Update Chrome now to protect against an actively exploited vulnerability
Google shipped Chrome 153.0.8010.36/.37 fixing 230 flaws including actively exploited V8 out-of-bounds write CVE-2026-87491 enabling sandboxed code execution.
Chrome stable channel updated to 153.0.8010.36/.37 for Windows and Mac and 153.0.8010.36 for Linux, including 230 security fixes. CVE-2026-87491 is an out-of-bounds write in Chrome's V8 JavaScript engine that a crafted HTML page can exploit to execute arbitrary code inside the browser sandbox; Google rates it medium severity, but it is confirmed as actively exploited. The update also fixes five Critical vulnerabilities, four of which were found in WebGL. Users should update via Settings > About Chrome and restart the browser.
Google fixes the sixth actively exploited Chrome zero
Google patched 12 Chrome flaws including actively exploited V8 type confusion zero-day CVE-2026-85046 (CVSS 8.8), enabling sandboxed remote code execution via crafted webpages.
Google released Chrome Stable 152.0.7977.82/.83 for Windows and Mac and 152.0.7977.82 for Linux, fixing 12 vulnerabilities including CVE-2026-85046, a type confusion in V8 with a CVSS score of 8.8. Google says an exploit exists in the wild, making this the sixth actively exploited Chrome zero-day of 2026. The bug affects the JavaScript and WebAssembly engine and allows arbitrary code execution inside the browser sandbox via a specially crafted HTML page. Researcher Salvatore Gulizia (Serotav) reported the flaw on August 4, 2026 and received a $1,000 bounty.
⚡ Weekly Recap: VMware Exploits, Windows 0-Day, MCP Attacks, Browser Hijacks and More
Weekly recap: suspected China-nexus APT exploited VMware vCenter CVE-2026-59310, Lazarus used Windows zero-day CVE-2026-68820, and macOS flaw dropped Monero miners.
The week's top stories included a suspected China-nexus APT exploiting VMware vCenter CVE-2026-59310 (CVSS 9.8), a directory-traversal flaw enabling arbitrary code execution, with backdoors, reverse SSH and Babuk-derived ransomware deployed, per QUIRSO. NCSC-NL reported active exploitation of macOS Screen Sharing flaw CVE-2026-65400 (CVSS 9.8) to install Monero miners on systems with port 5900 exposed. Lazarus Group exploited Windows zero-day CVE-2026-68820 (CVSS 7.0) in Operation Dream Job, delivering ForestTiger and Troy backdoors to defense and aerospace targets. GeoServer patched a critical SQL injection flaw exploited within hours of disclosure, and Jamf analyzed the new Amnesia Stealer for macOS with live browser control.
Attackers Actively Exploiting Critical Vulnerability in WooCommerce Wholesale Lead Capture Plugin
Attackers are actively exploiting an unauthenticated arbitrary file upload flaw in the WooCommerce Wholesale Lead Capture plugin, enabling PHP backdoors and remote code execution.
A critical unauthenticated arbitrary file upload vulnerability in WooCommerce Wholesale Lead Capture, a premium WordPress plugin with an estimated 6,000 active installations, was publicly disclosed on February 20, 2026. Wordfence reports attackers are now actively exploiting the flaw to upload arbitrary files, including PHP backdoors, and achieve remote code execution. No CVE ID was cited in the report.
Google fixes the seventh actively exploited Chrome zero-day of 2026
Google patched 230 Chrome flaws in version 153.0.8010.36, including actively exploited V8 out-of-bounds write CVE-2026-87491 (CVSS 8.8), the seventh 2026 Chrome zero-day.
Google released Chrome 153.0.8010.36 on Linux and 153.0.8010.36/.37 on Windows and Mac, fixing 230 security vulnerabilities. CVE-2026-87491, an out-of-bounds write in the V8 JavaScript and WebAssembly engine (CVSS 8.8), is being exploited in the wild through specially crafted HTML pages to execute arbitrary code inside Chrome's sandbox. Google says it is the seventh actively exploited Chrome zero-day of 2026, following CVE-2026-2441, CVE-2026-3909, CVE-2026-3910, CVE-2026-5281, CVE-2026-11645, and CVE-2026-85046. Researcher Jihyeon Jeong of Seoul National University reported it on 2026-08-06 and received a $2,500 bounty; Google disclosed no technical details or attribution.
Attackers Actively Exploiting Critical Vulnerability in Super Forms Plugin
Attackers are actively exploiting a critical unauthenticated file upload flaw in the Super Forms WordPress plugin to deploy PHP backdoors for RCE.
Wordfence disclosed on July 9, 2026 a critical unauthenticated arbitrary file upload vulnerability in the Super Forms WordPress plugin, which has roughly 13,000 active installations. Unauthenticated attackers can upload arbitrary files, including PHP backdoors, to achieve remote code execution. The vendor now reports that attackers are actively exploiting the flaw in the wild.
Critical Gitea RCE Actively Exploited as Reported Attack Drops Miner
CISA added actively exploited Gitea RCE CVE-2026-60004 (CVSS 9.8) to the KEV catalog as attackers deploy a cryptojacking dropper.
CVE-2026-60004 is a critical remote code execution flaw affecting Gitea versions 1.17 through 1.27.0, abused via the diffpatch endpoint to install a Git hook and execute shell commands as the Gitea OS user. Default open registration lets unauthenticated attackers obtain the required repository write access. CISA added the flaw to its Known Exploited Vulnerabilities catalog, giving federal agencies until August 28, 2026 to patch; version 1.27.1 fixes it. A developer reported their HOSTKEY-hosted VPS was exploited to run a miner-like dropper, driving CPU usage above 70% and killing competing processes.
CISA Warns of Zimbra OS Command Injection Vulnerability Active Exploitation (CVE-2026-73570)
CISA added actively exploited Zimbra OS command injection flaw CVE-2026-73570 to its KEV catalog, urging users to patch by August 24, 2026.
CISA warned that Zimbra vulnerability CVE-2026-73570 is being actively exploited in the wild and added it to its Known Exploited Vulnerabilities Catalog. The OS command injection flaw resides in the SNMP monitoring component and is exploitable when SNMP notifications are enabled. Users, including US federal agencies subject to BOD deadlines, were urged to apply fixes before the August 24, 2026 deadline. Qualys ThreatPROTECT published tracking coverage of the KEV addition.
CISA Flags Actively Exploited Ray Flaw That Can Trigger Browser
CISA added actively exploited Ray flaw CVE-2025-62593 (CVSS 9.4) to its KEV catalog; the DNS rebinding RCE has powered crypto-mining and DDoS botnet campaigns.
CISA added CVE-2025-62593 (CVSS 9.4) to its Known Exploited Vulnerabilities catalog, citing active exploitation of a DNS rebinding-driven RCE flaw in the Ray distributed computing framework, fixed in version 2.52.0. The flaw stems from missing authentication on critical Ray endpoints and an insufficient User-Agent header guard, exploitable against developers running Ray in Firefox or Safari via malicious websites or ads. RondoDox botnet operators incorporated the PoC exploit before the November 26, 2025 disclosure, and unpatched GPU-equipped clusters were hijacked into self-replicating crypto-mining botnets in the ShadowRay 2.0 campaign. FCEB agencies must apply fixes by August 20, 2026.
Android 0-day Vulnerability on Google Pixel Devices Actively Exploited in Attacks
Google patched CVE-2026-58704, an actively exploited Android zero-day allowing proximal privilege escalation via the Pixel cellular modem, urging the 2026-09-05 patch.
Google confirmed CVE-2026-58704, a high-severity elevation-of-privilege flaw in the Pixel cellular modem, is being exploited in limited, targeted attacks and shipped emergency fixes in the September 2026 Pixel Update Bulletin. The low-complexity bug requires no user interaction and enables proximal/adjacent privilege escalation with no additional execution privileges, phrasing Google has historically used for spyware-vendor and state-aligned zero-days. The Pixel bulletin patches 110 flaws including 12 critical RCEs, while the broader September Android update addressed roughly 180 vulnerabilities, including Wi-Fi memory-corruption bug CVE-2026-28662.
Google fixes yet another actively exploited Chrome zero-day (CVE-2026-87491)
Google patched actively exploited Chrome zero-day CVE-2026-87491, a V8 out-of-bounds write enabling sandboxed code execution, in Chrome 153.0.8010.36+.
Google fixed 230 Chrome vulnerabilities including CVE-2026-87491, a Medium-severity out-of-bounds write in the V8 JavaScript and WebAssembly engine that allows remote arbitrary code execution inside the sandbox via a crafted HTML page. Google confirmed an exploit exists in the wild; fixes shipped in Chrome 153.0.8010.36 and .37 for Windows and macOS and 153.0.8010.36 for Linux. The flaw was reported August 6, 2026 by Jihyeon Jeong of Seoul National University's Compsec Lab, earning a $2,500 bounty. It is the seventh actively exploited Chrome zero-day patched in 2026, following CVE-2026-2441, CVE-2026-3909, CVE-2026-3910, CVE-2026-5281, CVE-2026-11645 and CVE-2026-85046.
Attackers Chain Two PaperCut Flaws to Execute Code Without Authentication
Attackers chain PaperCut NG/MF flaws CVE-2026-81578 and CVE-2026-82078 for unauthenticated RCE; exploitation observed and a second emergency patch issued.
Two flaws in PaperCut NG and MF — CVE-2026-81578 (CVSS 8.8, improper access control enabling auth bypass) and CVE-2026-82078 (CVSS 9.4, unsafe dynamic class loading) — are being chained for unauthenticated remote code execution. Huntress observed limited exploitation on two customer environments, including Base64-encoded commands, 'whoami & ver' fingerprinting, SimpleHelp execution, and AnyDesk installation for persistence. PaperCut released a second emergency patch for v24, v25, and v26, but watchTowr reports additional patch bypasses may still affect the latest version. Shared IoCs include crafted jdbc strings in server.log and attacker-written .class/.cmd files.
Off the Hook: Discovering and Observing Active Exploitation of Sangoma Switchvox CVE-2026-9586
Horizon3 disclosed CVE-2026-9586, an unauthenticated SQL injection in Sangoma Switchvox leading to RCE, now under active exploitation in the wild.
Horizon3.ai attack researchers discovered CVE-2026-9586, an unauthenticated SQL injection vulnerability in Sangoma's Switchvox VoIP appliance that can escalate to remote code execution. The researchers observed active exploitation of the flaw in the wild. A disclosure write-up was published alongside their findings, and defenders should treat internet-exposed Switchvox instances as at risk.
Google patches actively exploited Chrome zero-day (CVE-2026-85046)
Google patches actively exploited Chrome zero-day CVE-2026-85046, a V8 type confusion bug enabling sandboxed code execution via crafted HTML pages.
Google patched 12 Chrome vulnerabilities, including CVE-2026-85046, a CVSS 8.8 type confusion flaw in the V8 JavaScript and WebAssembly engine exploited in the wild. The bug, reported by researcher Salvatore Gulizia (Serotav) on August 4, 2026, allows arbitrary code execution inside the sandbox via a crafted HTML page; the researcher described it as a V8 compiler bug enabling arbitrary read/write on the JavaScript heap. Fixes shipped in Chrome 152.0.7977.82/.83 for Windows and macOS and 152.0.7977.82 for Linux, and this is the sixth Chrome zero-day Google has fixed in 2026.
Hackers Are Probing PaperCut Servers, and 47% Still Have No Patch
PaperCut pre-auth RCE CVE-2026-81578 actively exploited; 47% of tracked installs unpatched and exposed to remote code execution.
Huntress confirmed active exploitation of a pre-authentication RCE flaw in PaperCut (CVE-2026-81578), chainable with CVE-2026-82078 to achieve SYSTEM-level code execution via PaperCut's Application Server. Observed attacks focused on short reconnaissance (whoami, ver, tasklist) with no persistence, but a malicious Java class dropping into the installation directory leaves the jdbc:derby:memory:pwn breadcrumb. Roughly 47% of ~2,500 tracked installations run version 23 or earlier with no patch yet available.
AI-Generated Exploit Scripts Target Siemens S7 PLCs in U.S. Critical Infrastructure
NSA, CISA, FBI, DOE and EPA warn that actors use AI-generated Python scripts to exploit internet-exposed Siemens S7 PLCs at U.S. critical infrastructure.
A joint advisory from NSA, CISA, FBI, DOE and EPA describes an active threat in which AI-generated exploit scripts disguised as legitimate monitoring tools target Siemens S7 Series PLCs (S7-200 through S7-1500, including F-series safety controllers). The actors use Censys and ZoomEye scanning to find internet-exposed, outdated PLCs and a custom Python script using snap7 libraries over the S7comm protocol for initial access, credential access and denial of service; no attribution was given. Targeted sectors include Critical Manufacturing, Energy, Water and Wastewater, Chemical, Food and Agriculture, and Commercial Facilities, with potential for process disruption and cascading impacts. A related Dream report details a near-autonomous AI-agent campaign (July 1-4, 2026, 12 waves) against Taiwan government entities, using Hermes and OpenClaw agents with eight parallel sub-agents to crack 85 accounts via password spraying and exfiltrate over 2,564 personnel records, SSO client secrets and database credentials.
N-able ships second N-central hotfix as attackers keep exploiting CVE-2026-18577
N-able shipped a second N-central hotfix as attackers actively exploit authentication bypass CVE-2026-18577, attributed to ransomware group Storm-1175.
N-able released Hotfix 2 (N-central 2026.3.1.10) to counter ongoing exploitation of CVE-2026-18577, an authentication bypass that evades the patch for the earlier CVE-2026-18556; exploitation was first detected on August 1, 2026. Post-exploitation includes using the Take Control feature to reach managed endpoints, registering a Cloudflare tunnel service for persistence, creating a 'veeam' domain account, resetting admin passwords, and disabling Microsoft and Sophos security tooling. Microsoft analysts link the activity to Storm-1175, which now deploys a new StormEncryptor ransomware strain instead of Medusa, often reaching data exfiltration and ransomware within days. Sophos and Huntress expanded the IOCs and warned that partners who patched late should treat environments as potentially compromised.