All news with #f5 tag

🔒 Researchers at DepthFirst AI found an 18-year-old heap buffer overflow in NGINX’s ngx_http_rewrite_module (CVE-2026-42945) that can cause denial of service and, under specific conditions, remote code execution. The flaw affects NGINX Open Source 0.6.27 through 1.30.0 and several F5-managed builds. Exploitation hinges on configurations using both rewrite and set directives and problems in the internal script engine’s two-pass handling of rewrites. Patches and mitigations are available, and F5 recommends replacing unnamed PCRE capture groups with named captures if immediate upgrades are not possible.

⚠️ F5 and researcher depthfirst disclosed a critical heap buffer overflow in the ngx_http_rewrite_module affecting both NGINX Plus and NGINX Open Source. Tracked as CVE-2026-42945 (CVSS v4: 9.2) and dubbed NGINX Rift, the flaw can be triggered remotely via crafted URIs to cause DoS or, with ASLR disabled, lead to remote code execution. Fixes were released after responsible disclosure on April 21, 2026, across many NGINX releases and ecosystem products. Users should apply vendor updates or replace unnamed PCRE captures with named captures as a temporary mitigation.

⚠️ Shadowserver reports over 14,000 Internet-exposed BIG-IP APM instances remain vulnerable to CVE-2025-53521 after the flaw was reclassified from DoS to remote code execution. F5 confirmed the reclassification and warned that attackers are exploiting unpatched systems with access policies on virtual servers. F5 and CISA have published IOCs and mitigation guidance, and F5 recommends rebuilding compromised devices from known-good sources.

⚠️ Five-month-old F5 BIG-IP APM flaw initially classified as a denial-of-service is now confirmed as a pre-authentication remote code execution vulnerability (CVE-2025-53521) being exploited in the wild. F5 updated its advisory, raised the CVSS to 9.8, and CISA added the issue to its KEV catalog after reports of active exploitation and observed root‑level malware persistence. Affected versions include 15.1.x, 16.1.x, 17.1.x and 17.5.x; F5 has released fixes, IOCs, and hardening guidance, but organizations should patch immediately and perform compromise assessments rather than rely solely on backups.

⚠️ The UK’s NCSC is urging organisations to immediately patch a critical vulnerability in F5 BIG-IP Access Policy Manager (APM) tracked as CVE-2025-53521, which is under active exploitation and can enable remote code execution when an APM access policy is configured on a virtual server. F5 has reclassified the issue from a denial‑of‑service to RCE with a revised CVSS of 9.8 after new information, and CISA has added it to its KEV catalog with a mandated federal patch deadline. Customers should follow F5’s incident‑handling and forensic guidance, isolate or rebuild affected systems, and report suspected compromises to the NCSC.

⚠️F5 Networks has reclassified a previously patched BIG-IP APM denial-of-service flaw (CVE-2025-53521) as a critical remote code execution vulnerability after evidence of active exploitation. Attackers are deploying webshells on unpatched devices that have access policies configured on virtual servers. F5 and CISA have published advisories and IOCs and are urging immediate patching, forensic checks of disks, logs, and terminal history, and adherence to incident-handling policies.

⚠️ CISA has added CVE-2025-53521 to its Known Exploited Vulnerabilities (KEV) list after evidence of active exploitation against F5 BIG-IP APM. The flaw, reclassified from a DoS to an RCE with a CVSS v4 score of 9.3, permits unauthenticated remote code execution when an APM access policy is configured on a virtual server. F5 published file, log, and traffic indicators and warned that webshells may run in memory. Organizations and FCEB agencies were directed to apply the vendor fixes by March 30, 2026.

⚠️ CISA has added CVE-2025-53521, a remote code execution vulnerability in F5 BIG-IP, to the Known Exploited Vulnerabilities (KEV) Catalog after evidence of active exploitation. The agency notes this class of flaw is a frequent attacker vector and poses significant risk to the federal enterprise. Under BOD 22-01, Federal Civilian Executive Branch agencies must remediate KEV entries by assigned due dates. CISA strongly urges all organizations to prioritize timely remediation, apply vendor fixes or mitigations, and maintain active monitoring to reduce exposure.

⚠️ F5 disclosed a major intrusion in which a sophisticated, likely nation-state threat actor maintained long-term access to its internal network. During the compromise the attackers gained control of the build and distribution environment for BIG-IP updates and exfiltrated proprietary source code, documentation of unpatched vulnerabilities, and customer configuration files. F5 warned this data could enable widespread supply-chain and targeted attacks against many sensitive networks.

🔒 This weekly recap highlights long-lived, stealthy intrusions and emerging tactics that are reshaping defender priorities. Chief among them, F5 disclosed a year-long breach involving the BRICKSTORM malware and stolen BIG-IP source material, while researchers uncovered new Linux rootkits such as LinkPro and campaigns abusing blockchain smart contracts for malware delivery. The report urges inventorying edge devices, prioritizing patches, and improving detection, baselining, and intelligence sharing.

⚠️ Shadowserver Foundation reports 266,978 internet-exposed F5 BIG-IP instances after F5 disclosed a breach in which nation-state actors stole source code and information on undisclosed BIG-IP flaws. F5 issued patches addressing 44 vulnerabilities and urged immediate updates for BIG-IP, F5OS, BIG-IQ, and related products. CISA issued an emergency directive requiring federal agencies to patch or mitigate affected devices by set deadlines. Nearly half of the detected instances are in the United States, with most others across Europe and Asia.

🔒 On Oct. 15, 2025, F5 disclosed a nation-state compromise that exfiltrated source code and undisclosed vulnerability information from the BIG-IP product development and engineering knowledge platforms. F5 reports no evidence of modification to its software supply chain or access to CRM, financial, support case management, iHealth, NGINX or distributed cloud products. Unit 42 warns the theft could accelerate exploit development and recommends immediate patching, hardening, and targeted threat hunting for anomalous admin activity and configuration changes.

🔒 F5 Networks acknowledged that a highly sophisticated threat actor exfiltrated portions of BIG-IP source code, information about undisclosed vulnerabilities, and configuration data for a small percentage of customers. The company says there is no evidence of modification to its build pipelines or active exploitation of undisclosed critical vulnerabilities. F5 has released security updates for BIG-IP, F5OS, BIG-IP Next for Kubernetes, BIG‑IQ, and APM clients and urges customers to apply them immediately. CISA has directed federal agencies to assess internet-exposed BIG-IP devices, and F5 will provide eligible customers a free subscription to CrowdStrike Falcon EDR.

🔒 F5 has released security updates for BIG-IP products to address vulnerabilities whose details were stolen during a state-linked breach detected on August 9, 2025. The vendor patched 44 issues across BIG-IP, F5OS, BIG-IP Next for Kubernetes, BIG-IQ, and APM clients and says it has not seen evidence the flaws were exploited or publicly disclosed. Customers are urged to apply updates immediately and follow F5's guidance to increase logging and monitoring.

🔒 F5 disclosed that unidentified threat actors accessed its systems and exfiltrated files including portions of BIG-IP source code and documentation on undisclosed product vulnerabilities. The company attributed the intrusion to a highly sophisticated nation-state threat actor, reported detection on August 9, 2025, and said it has contained the activity. F5 engaged Google Mandiant and CrowdStrike, rotated credentials, strengthened controls, and advised customers to apply updates to BIG-IP, F5OS, BIG-IQ, and APM clients.

🔒 F5 disclosed that nation-state attackers breached its systems and exfiltrated portions of BIG-IP source code and information about undisclosed vulnerabilities after gaining persistent access to product development and engineering knowledge platforms. The company says it first detected the intrusion on August 9, 2025, and has found no evidence the stolen data has been exploited or publicly disclosed. F5 reports that its software supply chain was not compromised and no suspicious code modifications were observed, while it continues identifying customers whose configuration or implementation details may have been taken.

🛡️ CISA has issued Emergency Directive 26-01 requiring Federal Civilian Executive Branch agencies to install vendor-provided updates for at-risk F5 devices and software — including F5OS, BIG-IP TMOS, BIG-IQ, and BNK/CNF — by October 22, 2025. The action responds to disclosure that a nation-state actor maintained persistent access to F5 development environments and exfiltrated files containing embedded credentials and API keys. CISA will assess and support agency adherence and urges all entities using these products to apply mitigations immediately.

⚠ CISA issued Emergency Directive ED 26-01 directing Federal Civilian Executive Branch agencies to inventory and secure F5 BIG-IP hardware and software, assess public internet exposure of management interfaces, and apply vendor patches. Agencies must update specified F5 products by Oct. 22, 2025 (other devices by Oct. 31) and submit inventories to CISA by Oct. 29, 2025. The directive responds to a nation-state actor compromise that exfiltrated BIG-IP source code and vulnerability data.

🔒 A Chinese state-sponsored group tracked as RedNovember carried out a global espionage campaign from June 2024 to July 2025, compromising defense contractors, government agencies, and major corporations by exploiting internet-facing network appliances. The attackers rapidly weaponized disclosed flaws in devices from SonicWall, Ivanti, Cisco, F5, Sophos, and Fortinet, often within 72 hours of public exploit code. They deployed Go-based tools including Pantegana, Cobalt Strike, and SparkRAT, and relied on open-source tooling and legitimate services to obfuscate attribution and maintain persistent access.