{"id":"CVE-2026-94127","published":"2026-09-22T15:17:24Z","modified":"2026-09-23T14:32:07Z","title":"F5 BIG-IP APM Heap-based Buffer Overflow Vulnerability","vendor":"F5","product":"BIG-IP APM","tier":"core","eol":null,"description":{"text":"When a BIG-IP APM access policy and an OAuth profile are configured on a virtual server, specific malicious traffic can lead to remote code execution (RCE). This vulnerability is only present when BIG-IP APM is configured as an OAuth Authorization Server. Deployments using APM strictly as an OAuth Client / Resource Server (without OAuth authorization server profiles configured) are not affected by this vulnerability.\n\nImpact:\nThis vulnerability allows an unauthenticated attacker to perform remote code execution. The BIG-IP system in Appliance mode is also vulnerable. This is a data plane issue; there is no control plane exposure.\n\n \n\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","provenance":"source","from":"NVD"},"summary":{"text":"The flaw is a heap-based buffer overflow in the OAuth Authorization Server functionality of F5 BIG-IP APM, which is affected only when an APM access policy and an OAuth profile are configured on a virtual server. An unauthenticated remote attacker can exploit it by sending specific malicious traffic to that virtual server, achieving remote code execution with no authentication or user interaction required, and the same applies to BIG-IP systems in Appliance mode.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-23T07:14:04Z"},"cvss":{"score":9.8,"severity":"CRITICAL","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.24938,"percentile":0.97912,"date":"2026-10-30","provenance":"source"},"kev":{"dateAdded":"2026-09-22","dueDate":"2026-09-25","ransomware":false,"requiredAction":"Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.","notes":"For temporary mitigation to allow for proactive forensic triage, apply the vendor-provided iRule. Once completed, install the final vendor patch as soon as possible. For more information please see: https://my.f5.com/manage/s/article/K000162605 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-94127","provenance":"source"},"vulncheckKev":{"dateAdded":"2026-09-22","exploitedFirstSeen":"2026-09-22","ransomware":false,"evidence":[{"url":"https://my.f5.com/manage/s/article/K000162605","date":"2026-09-22"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2026-09-22"}],"evidenceTotal":2,"provenance":"source"},"exploited":true,"otx":{"pulseCount":43,"pulses":[{"name":"Actively_Exploited_Kev | Oct 31, 2026","url":"https://otx.alienvault.com/pulse/6ae4aefab0c2191cecd41862","created":"2026-10-30"},{"name":"Actively_Exploited_Kev | Oct 30, 2026","url":"https://otx.alienvault.com/pulse/6ae35d889ea92b4ce19c2680","created":"2026-10-29"},{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"}],"provenance":"machine"},"cwes":[{"id":"CWE-122","name":"Heap-based Buffer Overflow"}],"references":[{"url":"https://my.f5.com/manage/s/article/K000162605","tags":["Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-94127","tags":["US Government Resource"]}],"techniques":[{"id":"T1190","name":"Exploit Public-Facing Application","tactics":["initial-access"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: unauthenticated network traffic exploits public-facing BIG-IP APM","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"specific malicious traffic can lead to remote code execution (RCE)","start":89,"end":155}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1059","name":"Command and Scripting Interpreter","tactics":["execution"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: RCE yields command/code execution on appliance","mappingType":"primary_impact","evidence":[{"from":"description","quote":"allows an unauthenticated attacker to perform remote code execution","start":449,"end":516}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2026-84427","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-84427","exploited":true,"exploitedSince":"2026-09-22","provenance":"source"},"exploits":[],"exploitSources":{"pocGithub":{"count":2,"skipped":0,"earliest":"2026-09-23","earliestUrl":"https://github.com/FurkanKAYAPINAR/CVE-2026-94127","repos":[{"name":"watchtowrlabs/watchTowr-vs-f5-bigip-PreAuth-RCE-CVE-2026-94127","url":"https://github.com/watchtowrlabs/watchTowr-vs-f5-bigip-PreAuth-RCE-CVE-2026-94127","stars":15,"created":"2026-09-24"},{"name":"FurkanKAYAPINAR/CVE-2026-94127","url":"https://github.com/FurkanKAYAPINAR/CVE-2026-94127","stars":0,"created":"2026-09-23"}]},"first":{"date":"2026-09-23","source":"PoC-in-GitHub","url":"https://github.com/FurkanKAYAPINAR/CVE-2026-94127"},"provenance":"source"},"exploitRefs":[],"flow":[{"stage":"exploitation","techniques":["T1190"],"provenance":"ai"},{"stage":"primary","techniques":["T1059"],"provenance":"ai"}],"timeline":[{"date":"2026-09-22","kind":"published","label":"Published (NVD)","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-94127","provenance":"source"},{"date":"2026-09-22","kind":"exploited-reported","label":"Exploitation first reported (VulnCheck KEV evidence)","url":"https://my.f5.com/manage/s/article/K000162605","provenance":"source"},{"date":"2026-09-22","kind":"kev","label":"Added to CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","provenance":"source"},{"date":"2026-09-22","kind":"euvd-exploited","label":"ENISA EUVD: exploited","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-84427","provenance":"source"},{"date":"2026-09-23","kind":"exploit-public","label":"First public exploit: PoC-in-GitHub","url":"https://github.com/FurkanKAYAPINAR/CVE-2026-94127","provenance":"source"}],"speed":{"daysToPublicExploit":1,"firstExploitFrom":"PoC-in-GitHub","daysToKev":0},"priority":{"score":79.4,"factors":[{"name":"In a KEV catalog","points":35.0,"detail":"listed in CISA KEV and VulnCheck KEV"},{"name":"Recent KEV listing","points":10.0,"detail":"added 39 days ago"},{"name":"Known ransomware use","points":0.0,"detail":"not known"},{"name":"EPSS percentile","points":19.58,"detail":"percentile 0.9791"},{"name":"Named in threat reports","points":0.0,"detail":"0 reports"},{"name":"Public exploit code","points":5.0,"detail":"2 PoC-in-GitHub repos"},{"name":"Mentioned in OTX pulses","points":3.0,"detail":"43 pulses"},{"name":"CVSS severity","points":6.86,"detail":"base score 9.8"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]}}