# CVE-2026-121200 — Google Chrome

> As of 2026-11-06, CVE-2026-121200 is a CRITICAL-severity vulnerability in Google Chrome, CVSS v3.1 9.6, EPSS 0.3% (30.8th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-121200, most recently “Multiple Vulnerabilities in Google Chrome prior to 157.0.8103.38 (CVE-2026-121029 through CVE-2026-121257) - HK GovCERT Alert A26-11-05”.

**Last updated:** 2026-11-05

## What is CVE-2026-121200?

Incorrect reference resolution in DevTools in Google Chrome prior to 157.0.8103.38 allowed a remote attacker leveraging social engineering to potentially execute arbitrary code outside the sandbox via a crafted HTML page. (Chromium security severity: Medium)

The record classifies CVE-2026-121200 under weakness class [CWE-706](https://cwe.mitre.org/data/definitions/706.html). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs a user to take an action first, and has high impact on confidentiality, integrity, availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 4 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 9.6 — CRITICAL (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H`)
- **EPSS (FIRST):** 0.3% probability of exploitation in the next 30 days, higher than 30.8% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 6/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-11-03, last modified 2026-11-05

## Is CVE-2026-121200 being exploited?

It currently carries a trending score of 42 in the Threadlinqs vulnerability feed.

## Affected products and versions

- [Google](https://intel.threadlinqs.com/vendors/google): Chrome

## How to fix CVE-2026-121200

Vendor advisory: [https://chromereleases.googleblog.com/2026/11/stable-channel-update-for-desktop.html](https://chromereleases.googleblog.com/2026/11/stable-channel-update-for-desktop.html). Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.

## Threat activity tracking CVE-2026-121200

1 tracked threat in the Threadlinqs corpus references CVE-2026-121200, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Multiple Vulnerabilities in Google Chrome prior to 157.0.8103.38 (CVE-2026-121029 through CVE-2026-121257) - HK GovCERT Alert A26-11-05](https://intel.threadlinqs.com/threat/TL-2026-5449) — HIGH · 2026-11-06

## Sources

Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories. Last verified by Threadlinqs on 2026-11-07. This product uses the NVD API but is not endorsed or certified by the NVD.

**Other references**

- [chromereleases.googleblog.com](https://chromereleases.googleblog.com/2026/11/stable-channel-update-for-desktop.html)
- [issues.chromium.org](https://issues.chromium.org/issues/528485835)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-121200
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