Vulnerability · Published Nov 3, 2026 · Assigned by Chrome
CVE-2026-121039
Medium 5.3
In plain English
A medium-severity incorrect authorization in Chrome from Google. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 2% of all known vulnerabilities).
Severity (CVSS 3.1)5.3Medium
Exploit odds (30 days)0.1%top 98.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Incorrect authorization in Proxy Auth in Google Chrome prior to 157.0.8103.38 allowed an adjacent attacker to obtain sensitive information via crafted network traffic. (Chromium security severity: Medium)
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | chromium | no fix listed | DEBIAN-CVE-2026-121039 |
| Debian:13 | chromium | no fix listed | DEBIAN-CVE-2026-121039 |
| Debian:14 | chromium | no fix listed | DEBIAN-CVE-2026-121039 |
Affected products (as reported)
Weakness: CWE-863 · Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N