Public proof of conceptFix available

CVE-2026-111497

Q: Is CVE-2026-111497 actively exploited?

Yes. CVE-2026-111497 has been observed in active exploitation according to SSVC analysis.

Q: What is the CVSS score for CVE-2026-111497?

CVE-2026-111497 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Node2Shell: Out-of-Bounds Write in Google Brotli Decoder

A public proof of concept exists; no exploitation attested.

Published2026-10-22
Fixed in1.2.1 · 1.1.1 · 1.0.10
WeaknessCWE-252 · CWE-787

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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. 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.

Timeline

dates in UTC

2026-10-2214:17CVE publishedNVD
2026-10-2318:46First public proof of conceptPoC-in-GitHub
2026-10-2523:12EPSS crossed 10 %FIRST EPSS

Observed activity

isMalicious corpus · updated 2026-10-28 15:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-111497?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-111497?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD · OSV

Google brotli

Branch	Affected	Fixed in	Source
1.2	≥ 1.2.0, < 1.2.1	1.2.1	NVD
1.2	< 1.2.1	1.2.1	OSV
1.x	≥ 1.0.3, < 1.2.1	1.2.1	OSV
1.1	≥ 1.1.0, < 1.1.1	1.1.1	NVD
1.0	≥ 1.0.3, < 1.0.10	1.0.10	NVD

Microsoft .net

Branch	Affected	Fixed in	Source
10.0	≥ 10.0.0, < 10.0.14	10.0.14	NVD
9.0	≥ 9.0.0, < 9.0.22	9.0.22	NVD
8.0	≥ 8.0.0, < 8.0.33	8.0.33	NVD
11.0	= 11.0.0	no fix published	NVD

Node.js

Branch	Affected	Fixed in	Source
26.12	≥ 25.0.0, < 26.12.1	26.12.1	NVD
26.x	≥ 26.0.0, < 26.12.1	26.12.1	OSV
24.22	≥ 23.0.0, < 24.22.1	24.22.1	NVD · OSV
22.23	< 22.23.4	22.23.4	NVD · OSV

13 more products in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

brotliAlmaLinux:10all versions · fixed in 1.1.0-8.el10_2.1and 3 other packages
brotliAlmaLinux:9all versions · fixed in 1.0.9-10.el9_8.1and 3 other packages
brotliAlmaLinux:8all versions · fixed in 1.0.6-5.el8_10and 2 other packages

Vendor advisories

CVE-2026-111497 Red Hat Product Security479 products fixed · 87 known affected
brotli: Out-of-Bounds Write in Google Brotli Decoder
exploit-intelligence/vulnerability-analysis-rhel9 as a component of Exploit Intelligence · istio-proxy-selinux as a component of OpenShift Service Mesh 3 · istio-proxy.src as a component of OpenShift Service Mesh 3 · +84 more
RHSA-2026:87420 Red Hat Product Security13 products fixed
Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update

Full record on NVD

Fix

Update Google brotli to 1.2.1 · 1.1.1 · 1.0.10
Vendor fix Red Hat Product Security CVE-2026-111497 · 8 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
Vendor fix Red Hat Product Security RHSA-2026:87420 · 13 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
Workaround from the vendor Red Hat Product Security RHSA-2026:87420 · 13 productsSee the security bulletin for a detailed mitigation procedure.

Advisories and patches

github.comRelease Notes
github.comMitigation
github.comRelease Notes
github.comRelease Notes
github.comRelease Notes

Detection

read 2026-10-28 00:45 UTC

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: 20 repositories, unverifiedCaterMaoZi/CVE-2026-111497-POCdimasma0305/CVE-2026-111497-POCSami-AlEsh/nodejs-security-checkhypnguyen1209/CVE-2026-111497AdapptOnAzure/cve-2026-111497-mitigation

Sources

CISA-ADPSSVC decisionnone2026-10-23
OpenCVESSVC decisionactive—
CNACVSS 4.09.2read 2026-10-28
NVDCVSS 3.19.8read 2026-10-28
CNAweakness (CWE)CWE-252, CWE-787read 2026-10-28
FIRST EPSSEPSS score36.0 %read 2026-10-28
PoC-in-GitHubproof of concept20read 2026-10-28
OSVaffected packages—

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 4.0 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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Published: 2026-10-22
Last Modified: 2026-10-28
NVD status: Analyzed

Frequently asked questions

What is CVE-2026-111497?

Is CVE-2026-111497 actively exploited?

Yes. CVE-2026-111497 has been observed in active exploitation according to SSVC analysis.

What is the CVSS score for CVE-2026-111497?

CVE-2026-111497 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Running brotli? Hear about its next vulnerability

Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».

Get alerts for this product CISA KEV additions, October 2026 Search CVEs

No credit card required · No monthly cap on website lookups · 250 API requests/month

Go further

Following what attackers exploit right now? The CISA KEV additions of the month, with their patch deadlines.
Running this software? Vulnerability monitoring alerts you to new vulnerabilities in your products.

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database