CVE-2026-111497: Out-Of-Bounds Write Flaw in Google Brotli Scores 9.2 on CVSS
A newly published critical vulnerability in Google Brotli carries a CVSS score of 9.2. Here is what is affected and how to respond.
Key points
- CVE-2026-111497 affects Google Brotli.
- CVSS 9.2 (Critical).
- No exploitation confirmed yet.
Google Brotli is affected by CVE-2026-111497, a out-of-bounds write that the National Vulnerability Database rates 9.2 out of 10.
At a glance
- CVE
- CVE-2026-111497
- Product
- Google Brotli
- CVSS
- 9.2 Critical
- Weakness
- out-of-bounds write
- Exploited
- No known exploitation
What is the vulnerability?
The NVD entry states: 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.
Affected versions
| Vendor | Product | Versions |
|---|---|---|
| Brotli | before 1.0.10, before 1.1.1, before 1.2.1 |
Is it being exploited?
There is no public confirmation of exploitation at the time of publication. It does not appear in CISA's Known Exploited Vulnerabilities catalog. We will update this report if that changes.
What should you do?
- Identify whether the affected product and versions run in your environment.
- Apply the vendor update listed in the advisory as soon as it is available.
- Limit network exposure of the affected service until it is patched.
- Monitor the vendor advisory for updated guidance or exploitation reports.
What to do and how to stay safe: CVE-2026-111497
- Vulnerability severity scores ignore your specific architecture and context.
- Exploitability depends on network exposure and user behavior, not just code flaws.
- Prioritization requires continuous asset inventory and threat intelligence alignment.
Risk-based vulnerability management focuses your limited resources on the flaws that actually threaten your business. Start by mapping your critical assets and checking for active exploits to prioritize your backlog.
Step-by-step guide: Risk-Based Vulnerability Management: Prioritize Fixes by Actual Danger
General security guidance from the Threat Times newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
What is CVE-2026-111497?
CVE-2026-111497 is a out-of-bounds write vulnerability in Google Brotli.
How severe is CVE-2026-111497?
It has a CVSS score of 9.2 Critical.
Is CVE-2026-111497 being exploited?
There is no public confirmation of exploitation at the time of publication.
