{"schemaVersion":3,"id":"CVE-2026-93479","aliases":["DEBIAN-CVE-2026-93479","UBUNTU-CVE-2026-93479"],"status":"published","duplicateOf":null,"title":null,"description":"A vulnerability exists in NGINX Plus and NGINX Open Source when a map directive uses regex matching and the root directive or access log format references the map's regex capture variables before referencing the map output variable. Alternatively, the same result could be achieved by using a non-cacheable variable in a string expression under certain conditions. An unauthenticated attacker along with conditions beyond their control can exploit this vulnerability by sending crafted HTTP requests. This may cause a heap buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR.\n\nImpact:\nThis vulnerability may allow remote attackers to cause a denial-of-service (DoS) on the NGINX system or to possibly trigger a code execution. There is no control plane exposure; this is a data plane issue only.\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","dates":{"published":"2026-10-14T14:40:27.107Z","modified":"2026-10-15T10:31:15.685Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":9.2,"severity":"critical","version":"4.0","versionLabel":"v4.0","source":"CVE.org","vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"4.0","versionLabel":"v4.0","source":"CVE.org","score":9.2,"severity":"critical","vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":8.1,"severity":"high","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"4.0","versionLabel":"v4.0","source":"NVD","score":9.2,"severity":"critical","vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":8.1,"severity":"high","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"4.0","versionLabel":"v4.0","source":"OSV 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Buffer Overflow","description":"A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().","type":"weakness","status":"Draft","abstraction":"Variant","likelihoodOfExploit":"High","url":"https://cwe.mitre.org/data/definitions/122.html"}],"affected":[{"vendor":"debian","product":"nginx","name":"nginx","label":"nginx","ecosystem":"Debian","cpePart":null,"purl":"pkg:deb/debian/nginx","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null},{"text":"< 1.30.4-8","noFixRecorded":false,"fixedIn":null}],"versionsText":"All versions (No fix recorded) | < 1.30.4-8","eol":null,"hubHref":null},{"vendor":"ubuntu","product":"nginx","name":"nginx","label":"nginx","ecosystem":"Ubuntu","cpePart":null,"purl":"pkg:deb/ubuntu/nginx","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"All versions (No fix recorded)","eol":null,"hubHref":null},{"vendor":"f5","product":"nginx open source","name":"NGINX Open Source","label":"nginx open source","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≥ 1.31.2, < 1.31.7","noFixRecorded":false,"fixedIn":null},{"text":"≥ 1.30.0, < 1.30.6","noFixRecorded":false,"fixedIn":null}],"versionsText":"≥ 1.31.2, < 1.31.7 | ≥ 1.30.0, < 1.30.6","eol":null,"hubHref":"/vendor/f5/nginx_open_source"},{"vendor":"f5","product":"nginx plus","name":"NGINX Plus","label":"nginx plus","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≥ 37.1.0, < 37.1.0.1","noFixRecorded":false,"fixedIn":null},{"text":"≥ 37.0.0, < 37.0.5.1","noFixRecorded":false,"fixedIn":null},{"text":"≥ R36","noFixRecorded":true,"fixedIn":null},{"text":"≥ R35","noFixRecorded":true,"fixedIn":null},{"text":"≥ R34","noFixRecorded":true,"fixedIn":null},{"text":"≥ R33","noFixRecorded":true,"fixedIn":null}],"versionsText":"≥ 37.1.0, < 37.1.0.1 | ≥ 37.0.0, < 37.0.5.1 | ≥ R36 (No fix recorded) | ≥ R35 (No fix recorded) | ≥ R34 (No fix recorded) | ≥ R33 (No fix recorded)","eol":null,"hubHref":"/vendor/f5/nginx_plus"}],"affectedCount":4,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://my.f5.com/manage/s/article/K000162607","label":"my.f5.com/manage/s/article/K000162607","hostname":"my.f5.com","tags":["Vendor Advisory","REPORT"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-93479","label":"security-tracker.debian.org/tracker/CVE-2026-93479","hostname":"security-tracker.debian.org","tags":["Advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-93479","label":"ubuntu.com/security/CVE-2026-93479","hostname":"ubuntu.com","tags":["REPORT"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-93479","label":"www.cve.org/CVERecord?id=CVE-2026-93479","hostname":"www.cve.org","tags":["REPORT"]}],"lineage":{"upstream":[],"downstream":["OPENSUSE-SU-2026:12143-1"],"duplicates":[],"related":["OPENSUSE-SU-2026:12143-1"]},"timeline":[{"kind":"published","date":"2026-10-14T14:40:27.107Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-10-15T10:31:15.685Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":70,"level":"high","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-19T08:22:09.266Z","stale":false,"partial":false}}