CVE-2026-111497
Google Brotli
Summary
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 mem…
Published: 2026-10-22 · In KEV since: 2026-10-27
Analysis
🔴 Critical — actively exploited
Weakness: Out-of-bounds Write (CWE-787). Writes memory outside the buffer; often enables RCE.
How it's exploited: Exploitable over the network (internet-reachable), unauthenticated, no user interaction, and with low complexity.
⚠️ Critical combo: remote, unauthenticated and no interaction → trivial to automate.
Impact: Full compromise (confidentiality, integrity and availability).
Status: Active exploitation confirmed by CISA (KEV).
- Patch now: it is in CISA's actively-exploited catalog (KEV), with a deadline.
- Reduce exposure: keep it off the internet; firewall, VPN or network segmentation.
- Detect: turn this CVE into detection rules.
CVSS 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
The vector encodes how it's exploited (translated above, in the analysis). Break it down in the CVSS tool →
Sources: CISA KEV · EPSS · FIRST.org · NVD. Analysis derived from the CVSS vector and exploitation status (no AI). Informational; always verify against the vendor's official advisory.