{"id":"CVE-2026-111497","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-111497","generatedAt":"2026-10-28T03:58:48.795Z","title":"Google Brotli Unchecked Return Value Vulnerability","description":"A buffer overflow vulnerability in the Brotli decoder (c/dec/decode.c) in Google Brotli versions 1.0.3 through 1.2.0 on all platforms allows a remote unauthenticated attacker to corrupt adjacent decoder state memory, disclose sensitive memory contents, cause a denial of service, or potentially execute arbitrary code using a crafted Brotli-compressed stream.\n\n\n\n\n\nUsers need to update any Brotli libraries or binaries between 1.0.3 through 1.2.0 to the latest available version: 1.0.10 or 1.1.1 or 1.2.1.","published":"2026-10-22T14:17:37.000Z","lastModified":"2026-10-27T20:17:13.000Z","status":"Undergoing Analysis","sourceIdentifier":"cve-coordination@google.com","cvss":{"version":"4.0","score":9.2,"severity":"CRITICAL","vector":"CVSS:4.0/AV:N/AC:L/AT:P/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/M"},"cwe":["CWE-252","CWE-787"],"affected":[],"epss":{"score":0.55483,"percentile":0.9903,"date":"2026-10-27","history":[{"date":"2026-10-23","score":0.0048,"percentile":0.40511},{"date":"2026-10-25","score":0.32782,"percentile":0.98336},{"date":"2026-10-26","score":0.36027,"percentile":0.98463},{"date":"2026-10-27","score":0.55483,"percentile":0.9903}]},"kev":{"listed":true,"dateAdded":"2026-10-27","dueDate":"2026-11-10","knownRansomwareCampaignUse":"Unknown","notes":"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.\nThis vulnerability affects an open-source component, third-party library, protocol, or proprietary implementation that could be used by different products. For more information, please see: https://github.com/google/brotli/releases/tag/v1.2.1 ; ; 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-2026-111497"},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"Known to be exploited in the wild (CISA KEV, CISA remediation deadline 10 November 2026). Treat as an emergency change: patch or isolate now, then hunt for prior compromise."},"changes":[{"kind":"epss","label":"EPSS jump","at":"2026-10-27T00:00:00.000Z","detail":{"to":0.55483,"from":0.36027,"percentile":0.9903},"summary":"EPSS moved from 36.0% to 55.5% probability of exploitation in the next thirty days."},{"kind":"kev","label":"Added to KEV","at":"2026-10-27T00:00:00.000Z","detail":{"name":"Google Brotli Unchecked Return Value Vulnerability","vendor":"Google","dueDate":"2026-11-10","product":"Brotli","ransomware":"Unknown"},"summary":"Added to CISA KEV — known to be exploited; federal remediation due 2026-11-10."},{"kind":"epss","label":"EPSS jump","at":"2026-10-25T00:00:00.000Z","detail":{"to":0.32782,"from":0.0071,"percentile":0.98336},"summary":"EPSS moved from 0.7% to 32.8% probability of exploitation in the next thirty days."},{"kind":"new","label":"New CVE","at":"2026-10-22T14:17:37.000Z","detail":{"score":"9.2","severity":"CRITICAL","publishedAt":"2026-10-22T14:17:37.190Z"},"summary":"New CVE, critical severity (CVSS 9.2), EPSS 55.5%."}],"references":[{"url":"https://github.com/andybalholm/brotli/releases/tag/v1.2.7","source":"cve-coordination@google.com"},{"url":"https://nodejs.org/en/blog/vulnerability/october-2026-security-releases#nodejs-brotli-decoder-out-of-bounds-write-permits-remote-code-execution-cve-2026-111497---high","source":"cve-coordination@google.com"},{"url":"http://www.openwall.com/lists/oss-security/2026/10/23/25","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2026/10/24/6","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2026/10/26/12","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2026/10/26/13","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2026/10/26/16","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://broccoli2shell.com","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/advisories/GHSA-9v8h-qqgm-4m35","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/dotnet/announcements/issues/494","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/google/brotli/releases/tag/v1.0.10","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/google/brotli/releases/tag/v1.1.1","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/google/brotli/releases/tag/v1.2.1","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2026/10/msg00049.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://patchtheplanet.org/brotli","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.aikido.dev/blog/node2shell-nodejs-brotli-rce-cve-2026-111497","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://ellio.tech/en/blog/node2shell-cve-2026-111497-rce-on-stock-nodejs-builds/","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-111497","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-111497","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}