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Acronis warns of actively exploited flaw in its cPanel backup plugin

Acronis reports CVE-2026-87886, a CVSS 7.8 Linux privilege escalation in its cPanel/WHM and Plesk backup plugins, exploited in limited targeted attacks.

CVE-2026-87886 is a high-severity local privilege escalation flaw in Acronis Backup plugin for cPanel & WHM (fixed in 1.9.3 HF3) and the Plesk extension (fixed in 1.8.11). A low-privileged attacker can elevate permissions on a vulnerable Linux server to access or modify sensitive data without user interaction. Acronis says it detected exploitation in the wild in limited, targeted attacks based on a single customer report, with no IOCs published yet.

BleepingComputerupdated · 1d agofirst · 1d agoExploit / PoC in the wild 6 sourcesCVE-2026-87886

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Object Group Access Control List Bypass Vulnerabilities

Cisco patched ACL Object Group Search bypass flaws in ASA and FTD firewall software that let unauthenticated attackers reach protected networks.

Cisco disclosed multiple vulnerabilities in the ACL Object Group Search implementation of Secure Firewall ASA and FTD Software, caused by a logic error in populating group access control policies. An unauthenticated remote attacker could send traffic that should be blocked through the device, bypassing configured access controls. Cisco has released software updates; no exploitation is mentioned.

Cisco Security Advisories · 20h agoAdvisory 9 sources

CVE-2026-82431: Apache Storm Client: Authorization Bypass When nimbus.groups Is Configured Without nimbus.users

Apache Storm Client 3.0.0 ACL bypass lets every authenticated principal bypass restrictions when nimbus.groups is set without nimbus.users.

CVE-2026-82431 affects Apache Storm Client (org.apache.storm:storm-client) versions 3.0.0 before 3.1.0. SimpleACLAuthorizer returned early when nimbus.users was empty, before evaluating nimbus.groups. Operators restricting cluster access by group alone received no restriction, so any authenticated principal could execute user-level commands. Fixed in version 3.1.0.

oss-security · 3d agoVulnerabilityCVE-2026-82431

CVE-2026-86465: Apache Airflow Akeyless provider: Akeyless secrets backend: team-scope guard bypass via user-controlled key

Apache Airflow Akeyless provider before 0.3.1 lets DAG authors bypass team-scope guards and read other teams' secrets.

CVE-2026-86465 (moderate) affects apache-airflow-providers-akeyless before 0.3.1. The Akeyless secrets backend's team-scope guard can be bypassed with a user-controlled key: in multi-team deployments, a DAG author scoped to one team can supply a Variable key containing a path separator that resolves a secret belonging to another team.

oss-security · 1d agoVulnerabilityCVE-2026-86465

Off Guard: Breaking LiteLLM from authentication bypass to cloud compromise

Wiz found LiteLLM auth bypass (CVE-2026-59822) and post-auth RCE (CVE-2026-59821) chainable to cloud compromise; the bypass is in CISA KEV with in-the-wild exploitation.

Wiz scanned roughly 3,074 internet-facing LiteLLM deployments and found 9.6% accepted the default master key sk-1234 or required no authentication, making post-auth attacks effectively pre-auth. The MCP endpoint accepts any Bearer token and grants a valid session (CVE-2026-59822), confirmed exploited in the wild via honeypots and added to CISA's Known Exploited Vulnerabilities catalog. Custom code guardrails allow post-auth root-level RCE via exec(compile(...)) (CVE-2026-59821), while pass-through endpoints lack URL validation, enabling cloud credential theft in post-auth scenarios. All assigned vulnerabilities have been patched; the research was presented at DEF CON 34.

Wiz Blog · 7d agoExploit / PoC in the wildCVE-2026-59822CVE-2026-598212

Decoy Direction Optimization: A Post-Hoc Defense Against LLM Abliteration

Researchers introduce Decoy Direction Optimization, a cheap weight-editing defense that blinds refusal-direction ablation attacks against open-weight LLM safety guardrails.

Refusal Feature Ablation bypasses safety guardrails in open-weight LLMs by projecting out a linear refusal direction, often with high attack success rates. Decoy Direction Optimization injects a high-magnitude nonlinear decoy into MLP neurons so attackers' contrastive estimators ablate a harmless orthogonal feature instead. Evaluated across six model families, DDO keeps ASR below 10% under standard RFA and on Llama-3-8B-Instruct reduces Heretic weight-level attack ASR from 88.7% to 18%. It costs 30 to 450 times less per configuration than trained defense baselines.

The Model Proposes, the Code Disposes: A Pre-Registered Ablation of a Verifier-and-Acceptance Stage in an LLM-Orchestrated Offensive-Security Agent

Pre-registered ablation finds a model verifier stage in an LLM offensive-security agent suppresses findings; removing it eliminated suppression with precision tradeoff.

The paper evaluates a verifier-and-acceptance stage in an LLM-orchestrated offensive-security agent via a pre-registered 20-run confirmatory ablation and a 2x2 factorial study with 40 runs on vulnerable lab targets. Removing the stage eliminated pre-report suppression (median 2 vs 0 findings, p = 0.00003) but reduced model-blinded shipped precision (0.471 vs 0.353, p = 0.0087). Suppression was attributed to the model verifier rather than deterministic acceptance rules, and an instrumented canary recorded zero external contacts in all 60 runs. The full design retained 93.8% of model-adjudicated true candidates but failed its pre-registered non-inferiority floor of 0.90.

arXiv cs.CR · 2d agoResearch

How Fragile Is Safety Alignment at Frontier Scale? A Single-Direction Attack on a 320B MoE

Researchers show directional ablation breaks refusal in GLM-5.3-Flash, a 320B-parameter MoE, cutting refusal by 41–89 points across seven benchmarks.

The study extends directional ablation, a white-box attack that removes an aligned LLM's refusal behavior, from dense models up to ~70B parameters to GLM-5.3-Flash, a 320B-parameter mixture-of-experts model with 288 routed experts, four-wide hyper-connection residual, and block-FP8 quantization. Editing attention, dense, and routed-expert writers jointly removes 0.776 of refusal, with 74% of the effect existing only under the joint intervention; the conventional module-name-based recipe reaches only 0.066 and fails silently on MoE architectures. The attack yields 41–89 percentage-point reductions in refusal across seven harmful benchmarks with no detected capability change, and a category-concentrated refusal residue survives all edits at ranks 1 to 12.

arXiv cs.CR · 8d agoAI safety & security

Citrix urges customers to fix critical NetScaler authentication bypass (CVE-2026-19490)

Citrix patched a critical authentication bypass, CVE-2026-19490, in NetScaler Gateway and NetScaler ADC, urging customers to upgrade immediately.

Citrix has patched two flaws in NetScaler ADC and NetScaler Gateway. CVE-2026-19490 is a critical authentication bypass (CVSS v4.0 9.3) that works when the appliance is configured as an SSL VPN, ICA Proxy, CVPN, RDP Proxy Gateway or AAA virtual server, with additional conditions depending on firmware and SAML configuration. A second flaw, CVE-2026-19489 (CVSS 8.8), is a memory overflow that can cause denial of service when SIP ALG is enabled on LSN setups. Rapid7 had not observed exploitation as of August 19, 2026, but urged emergency patching; a signature-based mitigation is available via NetScaler Console.

SimpleHelp OpenID Connect Auth Bypass to RCE [CVE-2026-48558]

Metasploit adds a module chaining SimpleHelp OpenID Connect authentication bypass to remote code execution, tracked as CVE-2026-48558.

A commit to the Rapid7 Metasploit Framework (dee04cdb) adds an exploit module for CVE-2026-48558, an OpenID Connect authentication bypass in SimpleHelp that can be escalated to remote code execution. SimpleHelp is widely deployed remote access and remote support software, making the auth bypass a serious exposure for exposed deployments. The commit provides public exploit code but the listing does not state observed exploitation.

Cisco Secure Firewall Management Center Software Authentication Bypass Vulnerability

Cisco warns of a critical authentication bypass in Secure Firewall Management Center that lets unauthenticated attackers execute scripts and obtain root access.

A vulnerability in the web interface of Cisco Secure Firewall Management Center (FMC) Software allows an unauthenticated, remote attacker to bypass authentication and execute script files on an affected device to obtain root access to the underlying operating system. The flaw stems from an improper system process created at boot time and is triggered via crafted HTTP requests. If the FMC management interface does not have public internet access, the attack surface is limited.

Critical NetScaler Flaw Can Bypass Authentication on Certain Gateway and AAA Servers

Citrix patches critical NetScaler Gateway and AAA authentication bypass CVE-2026-19490 (CVSS 9.3) plus a SIP ALG memory overflow flaw; exploitation attempts observed.

Citrix fixed CVE-2026-19490 (CVSS 9.3), an authentication bypass affecting customer-managed NetScaler ADC and Gateway appliances configured as Gateway (SSL VPN, ICA Proxy, CVPN, RDP Proxy) or AAA virtual servers, and CVE-2026-19489 (CVSS 8.8), a memory overflow causing DoS when SIP ALG is enabled in Large Scale NAT groups. Updates are available in versions 14.1-73.32, 13.1-63.21, and corresponding FIPS/NDcPP builds, while Citrix-managed cloud services were already patched. The flaws were reported by Samarth Vashisht of JPMorgan Chase's penetration-testing team, and Previdian later observed 10 exploitation attempts against CVE-2026-19490 from six unique IP addresses in Australia, Germany, Japan, and the US, with no confirmed compromise.

Attackers Exploit PaperCut Flaws to Steal Credentials From Schools and Universities

Attackers exploit newly disclosed PaperCut auth bypass CVE-2026-81578 and RCE CVE-2026-82078 to steal credentials from schools and universities in the US and Europe.

Arctic Wolf observed threat actors chaining CVE-2026-81578 (authentication bypass) and CVE-2026-82078 (remote code execution) in PaperCut to execute commands, perform reconnaissance, and create privileged accounts on servers at K-12 schools and universities in the US and Europe. Post-exploitation includes registry hive collection with lsa_collect.exe delivered via certutil, Meterpreter Java payloads from 194.180.48.134, and searches of PaperCut config files for passwords, LDAP bindings, and tokens. Stolen logins could provide a pathway into other critical systems across compromised environments.

The Hacker News · 12d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-820781

LiteLLM Flaws Let Attackers Execute Code as Root and Steal Cloud Credentials

Wiz disclosed LiteLLM flaws including CVE-2026-59822 MCP auth bypass, now in CISA KEV, enabling root RCE and AWS credential theft from exposed gateways.

Wiz researchers disclosed weaknesses in the open-source LiteLLM AI gateway: CVE-2026-59821 allows authenticated administrators to execute code as root via the Custom Code Guardrails feature, while CVE-2026-59822 is an MCP authentication bypass where a meaningless Bearer token establishes a valid session. The MCP bypass was observed in the wild through Wiz honeypots and added to CISA's Known Exploited Vulnerabilities catalog on September 2. A scan of 3,074 internet-facing instances found 294 (9.6%) accepting the default master key sk-1234 or lacking authentication. Fixes shipped in LiteLLM 1.82.0 (guardrail hardening) and 1.84.0 (MCP bypass); exposed instances can leak provider API keys and temporary AWS IAM credentials via the pass-through feature and metadata service, with a related config-check issue tracked as CVE-2026-35029.

Critical ArangoDB Flaws Allow Authentication Bypass and Remote Code Execution as Root

Two critical ArangoDB flaws (CVSS 9.8 and 9.9) enable unauthenticated API access and root code execution; fixes shipped in version 3.12.11

Remedio researchers found two ArangoDB flaws: GHSA-rrgq-978q-36mq (CVSS 9.8), an authentication bypass caused by the server inconsistently interpreting URL-encoded '/_api' paths, and GHSA-rvhw-4hpw-9vrx (CVSS 9.9), which lets users with database write access run JavaScript tasks with root privileges via the isSystem flag. Chained, they allow administrative database access without credentials, theft of the root password hash, and root code execution, exposing files such as /etc/shadow, TLS keys and cluster signing material on the official container image. ArangoDB shipped fixes in version 3.12.11 on August 31, 2026, with advisories published September 6; CVE identifiers were still pending. Users on 3.12.10.1 or earlier should upgrade, restrict exposure and rotate potentially exposed credentials.

Cyber Security News · 7d agoVulnerability

ZDI-26-533: Cisco Secure Firewall Management Center login.cgi Authentication Bypass Vulnerability

ZDI discloses CVE-2026-20316, a 9.8-rated unauthenticated authentication bypass in Cisco Secure Firewall Management Center login.cgi.

ZDI-26-533 describes an authentication bypass vulnerability in Cisco Secure Firewall Management Center's login.cgi that allows remote attackers to bypass authentication without any credentials. ZDI assigned a CVSS score of 9.8, and the flaw is tracked as CVE-2026-20316. As a central management plane for firewall infrastructure, compromise could enable broad policy changes.

ZDI Published Advisories · Aug 11, 2026VulnerabilityCVE-2026-20316

CVE-2026-75156: Apache Airflow FAB provider: FAB Azure AD OAuth: id_token issuer/audience not validated — cross-tenant authentication bypass

Apache Airflow FAB provider flaw (CVE-2026-75156) lets attackers bypass Azure AD OAuth token validation via unvalidated issuer and audience claims.

Apache Airflow FAB provider versions 3.7.3 through 3.8.0 do not validate the issuer or audience of Azure AD id_tokens during OAuth login, enabling cross-tenant authentication bypass. The issue affects deployments where the FAB auth manager is configured with Azure AD as an OAuth provider. A fix is available in version 3.8.1. Severity is rated moderate.

oss-security · 8d agoVulnerabilityCVE-2026-75156

Organizations Warned of Cisco Secure FMC Exploitation

Cisco and CISA warn that critical FMC authentication bypass CVE-2026-20079 is actively exploited; CISA added it to the KEV catalog with a September 12 deadline.

Cisco and CISA flagged active exploitation of CVE-2026-20079, a critical authentication bypass in Cisco Secure Firewall Management Center allowing remote, unauthenticated attackers to run malicious scripts and gain root access via crafted HTTP requests. Cisco patched the flaw in early March and added IoCs in late July, but confirmed active exploitation in its September 9 advisory; CISA added it to the KEV catalog requiring federal remediation by September 12. Talos identified three activity clusters exploiting CVE-2026-20079 and CVE-2026-20316, including state-sponsored and financially motivated actors, and this is the third FMC vulnerability in KEV this year after CVE-2026-20316 and CVE-2026-20131.

Cisco FMC CVE-2026-20079 Actively Exploited

Cisco confirms active exploitation of CVE-2026-20079, a maximum-severity authentication bypass in Secure Firewall Management Center.

Cisco has confirmed that CVE-2026-20079, a critical authentication bypass in Cisco Secure Firewall Management Center (FMC), is being actively exploited in the wild. The vulnerability carries a maximum CVSS severity, and defenders are urged to treat it as an urgent patch priority. FMC centrally manages Cisco Secure Firewall deployments, so exposure across enterprise environments is likely.

SOCRadar · 7d agoExploit / PoC in the wildCVE-2026-20079

Cisco BroadWorks CommPilot Application Software Authorization Bypass Vulnerability

Cisco patched a BroadWorks CommPilot authorization bypass letting low-privileged authenticated users alter device configurations via crafted HTTP requests.

A vulnerability in the web-based management interface of Cisco BroadWorks CommPilot Application Software is caused by missing authorization checks. An authenticated remote attacker with low privileges can send crafted HTTP requests to alter configurations on select pages. Cisco has released software updates and no workarounds are available.

Cisco Security Advisories · 20h agoAdvisory

ShieldCrash PoC: Microsoft Defender Fix Bypass

A ShieldCrash proof-of-concept bypasses Microsoft's patch for CVE-2026-69414, a high-severity elevation-of-privilege flaw in the Microsoft Malware Protection Engine.

Microsoft previously fixed CVE-2026-69414 (ShieldBreak), a high-severity elevation-of-privilege vulnerability in the Microsoft Malware Protection Engine used by Microsoft Defender. SOCRadar now reports a new proof-of-concept dubbed ShieldCrash demonstrating that the published fix can be bypassed. The available source text does not detail affected versions or whether the bypass has been used in real attacks.

SOCRadar · 7d agoExploit / PoCCVE-2026-69414

CVE-2026-86206, CVE-2026-86207: N-able N-central Authentication Bypass (FIXED)

Rapid7 disclosed two chained N-able N-central flaws, CVE-2026-86206 and CVE-2026-86207, enabling unauthenticated admin account creation; patched in 2026.3 Hotfix 3.

Rapid7 researchers found CVE-2026-86206 (semicolon/Forwarded access-control bypass, CWE-791, CVSSv4 6.9) and CVE-2026-86207 (UserTwoFactorLogin authentication bypass, CWE-305, CVSSv4 7.7) in the latest N-able N-central. Chained, they let a remote unauthenticated attacker create an attacker-controlled System administrator account. The bugs stem from Envoy and Jetty disagreeing on the requested path and whether the client is local. N-able patched both in N-central 2026.3 Hotfix 3, following the earlier CVE-2026-18577 authentication bypass.

2026-010: Critical Vulnerabilities in Citrix NetScaler ADC and NetScaler Gateway

Citrix patched NetScaler ADC/Gateway: auth bypass CVE-2026-19490 (CVSS 9.3) on Gateway/AAA configs and memory overflow CVE-2026-19489 (CVSS 8.8) requiring SIP ALG.

On 19 August 2026 Citrix published an advisory fixing two critical-severity issues in NetScaler ADC and NetScaler Gateway versions 14.1 before 14.1-73.32 and 13.1 before 13.1-63.21, plus FIPS/NDcPP builds. CVE-2026-19490 (CVSS 9.3) is an authentication bypass via alternate path, exploitable when the appliance is configured as a Gateway (SSL VPN, ICA Proxy, CVPN, RDP Proxy) or AAA virtual server, with a SAML action condition on newer builds. CVE-2026-19489 (CVSS 8.8) is a memory overflow causing unpredictable behaviour or denial of service, requiring SIP ALG enabled on a Large Scale NAT group. CERT-EU recommends applying updated builds as soon as possible.

CERT-EU Advisoriesupdated · 12d agofirst · 29d agoVulnerability 3 sourcesCVE-2026-19489CVE-2026-19490

Critical ArangoDB Bugs Expose Entire Databases and Enable Remote Code Execution as Root

Two critical ArangoDB flaws (CVSS 9.8/9.9) allow unauthenticated API access and root-level code execution; fixed in 3.12.11.

Remedio researchers reported two critical ArangoDB flaws on August 23, 2026: an authentication bypass via URL-encoded underscores (%5f) in path parsing (GHSA-rrgq-978q-36mq, CVSS 9.8) and a task-execution flaw where a client-controlled isSystem flag lets JavaScript run in the internal context (GHSA-rvhw-4hpw-9vrx, CVSS 9.9). Chained, they allow unauthenticated database access, theft of root password hashes, and root-level code execution when arangod runs as root, such as in the official container image. Patches shipped August 31 in ArangoDB 3.12.11, with GitHub Security Advisories published September 6; CVE identifiers were pending at disclosure time.

GBHackers · 8d agoVulnerability1

Microsoft patches critical Entra ID vulnerability (CVE-2026-69836)

Microsoft patched critical Entra ID RCE CVE-2026-69836 (CVSS 10.0), fully mitigated server-side with no customer action; no in-the-wild exploitation confirmed.

Microsoft patched CVE-2026-69836, a critical (maximum CVSS 10.0) unauthenticated remote code execution flaw in Entra ID caused by deserialization of untrusted data over a network. Entra ID, formerly Azure Active Directory, is Microsoft's cloud identity service verifying logins and controlling access to Microsoft 365, Azure, and connected third-party apps. The flaw was discovered by Microsoft Principal Security Engineer Robert Fitzpatrick and fully mitigated server-side, requiring no customer action. Microsoft initially reported the bug as exploited, but later changed the status to 'no' and confirmed the vulnerability was not exploited in the wild.

Help Net Security · 24d agoVulnerabilityCVE-2026-69836

Analog Pin Directionality as an Exfiltration Attack Surface in Mixed-Signal ICs

Researchers demonstrate exfiltration through nominally input-only analog pins in mixed-signal ICs, recovering data at 10 kbps on a 55nm PPG front-end.

The paper identifies a directionality-based attack class in analog/mixed-signal (AMS) ICs where data-dependent circuit-offset modulation converts a nominally input-only pin into an outbound information channel. Three host conditions enable the attack: a closed-loop amplifier, an exposed amplifier input, and sufficiently high impedance at that pin. Silicon validation on a photoplethysmography analog front-end in 55nm CMOS showed exfiltration at up to 10 kbps with error-free PRBS recovery, under 0.001% area overhead, and only 0.03 dB SNR reduction.

arXiv cs.CR · 18h agoResearch

USN-8736-2: Perl vulnerabilities

Ubuntu issued USN-8736-2 fixing two Perl regex flaws that could cause out-of-bounds heap access, denial of service, or security bypass on 24.04 LTS.

USN-8736-2 backports the Perl fixes from USN-8736-1 to Ubuntu 24.04 LTS. CVE-2026-15534 involves out-of-bounds heap reads or writes when regular expressions handle large inputs, potentially causing denial of service or arbitrary code execution. CVE-2026-19487 causes incorrect regex matching with alternative branches, allowing security restrictions to be bypassed.

Ubuntu Security Noticesupdated · 16h agofirst · 21h agoAdvisory 7 sourcesCVE-2026-15534CVE-2026-19487