CVE-2026-111497: Google Brotli Unchecked Return Value Vulnerability

CISA Known Exploited Vulnerabilities

Name

Google Brotli Unchecked Return Value Vulnerability

Vendor

Google

Product

Brotli

Added to the catalog

2026-10-27

Due date for US federal agencies

2026-11-10

Weaknesses

CWE-252, CWE-787

Catalog version

2026.10.30

Google Brotli contains an unchecked return value vulnerability that 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.

Required action (CISA)

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.

Ransomware use: CISA does not mark known use of this vulnerability in ransomware campaigns.

Links in CISA's notes

• https://github.com/google/brotli/releases/tag/v1.2.1
• https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk
• 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

Read on 2026-11-02T23:39:54.475Z under licence cisa-kev-cc0@b0067899 from https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json

NVD analysis

Status

Analyzed

Published

2026-10-22T14:17:37.190

Last modified

2026-10-30T20:30:11.670

Weaknesses

CWE-252, CWE-787

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.





Users 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.

References

• https://github.com/andybalholm/brotli/releases/tag/v1.2.7 (Release Notes)
• 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 (Third Party Advisory)
• http://www.openwall.com/lists/oss-security/2026/10/23/25 (Mailing List, Third Party Advisory)
• http://www.openwall.com/lists/oss-security/2026/10/24/6 (Mailing List, Third Party Advisory)
• http://www.openwall.com/lists/oss-security/2026/10/26/12 (Mailing List, Third Party Advisory)
• http://www.openwall.com/lists/oss-security/2026/10/26/13 (Mailing List, Third Party Advisory)
• http://www.openwall.com/lists/oss-security/2026/10/26/16 (Mailing List, Third Party Advisory)
• https://broccoli2shell.com (Third Party Advisory)
• https://github.com/advisories/GHSA-9v8h-qqgm-4m35 (Third Party Advisory)
• https://github.com/dotnet/announcements/issues/494 (Issue Tracking, Mitigation, Third Party Advisory)
• https://github.com/google/brotli/releases/tag/v1.0.10 (Release Notes)
• https://github.com/google/brotli/releases/tag/v1.1.1 (Release Notes)
• https://github.com/google/brotli/releases/tag/v1.2.1 (Release Notes)
• https://lists.debian.org/debian-lts-announce/2026/10/msg00049.html (Mailing List, Third Party Advisory)
• https://patchtheplanet.org/brotli (Third Party Advisory)
• https://www.aikido.dev/blog/node2shell-nodejs-brotli-rce-cve-2026-111497 (Third Party Advisory)
• https://cert-portal.siemens.com/productcert/html/ssa-045512.html (Third Party Advisory)
• https://cert-portal.siemens.com/productcert/html/ssa-443410.html (Third Party Advisory)
• https://cert-portal.siemens.com/productcert/html/ssa-898633.html (Third Party Advisory)
• https://ellio.tech/en/blog/node2shell-cve-2026-111497-rce-on-stock-nodejs-builds/ (Third Party Advisory)
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-111497 (US Government Resource)

This product uses the NVD API but is not endorsed or certified by the NVD.

Read on 2026-11-02T23:42:31.494Z under licence nvd-api-terms-of-use@ff2a5288 from https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-111497

CVE record

Title (CNA)

Out-of-Bounds Write in Google Brotli Decoder

Assigner

Google

State

PUBLISHED

Published

2026-10-22T13:35:41.975Z

Updated

2026-10-30T18:31:38.139Z

Problem types

CWE-787 Out-of-bounds Write; CWE-252 Unchecked Return Value

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.





Users 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.

References

• 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
• https://github.com/andybalholm/brotli/releases/tag/v1.2.7

Read on 2026-11-03T02:18:30.923Z under licence cve-terms-of-use@81bfa2f3 from https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/111xxx/CVE-2026-111497.json

GitHub Advisory Database

Also known as / affected packages

Defensive techniques (MITRE D3FEND)

D3FEND maps these defensive techniques to the weakness (CWE) that NVD lists for this CVE, through the digital artifacts the weakness affects. D3FEND does not say they stop this vulnerability.

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