What is CVE-2026-12456?
Inappropriate implementation in Extensions in Google Chrome prior to 149.0.7827.155 allowed an attacker who convinced a user to install a malicious extension to bypass same origin policy via a crafted Chrome Extension. (Chromium security severity: High)
The record classifies CVE-2026-12456 under weakness class CWE-20. 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. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 133 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 4.2 — MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N - EPSS (FIRST)
- 0.1% probability of exploitation in the next 30 days, higher than 2.7% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 2.2/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-06-17
Is CVE-2026-12456 being exploited?
It currently carries a trending score of 7 in the Threadlinqs vulnerability feed.
Affected products and versions
- Google: Chrome
How to fix CVE-2026-12456
Vendor advisory: https://chromereleases.googleblog.com/2026/06/stable-channel-update-for-desktop_01750511403.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-2026-12456
1 tracked threat in the Threadlinqs corpus references CVE-2026-12456, either in the campaign’s CVE list or as an indicator on the campaign record.
Sources
Enriched from CVE.org, NVD, FIRST EPSS. Last verified by Threadlinqs on . This product uses the NVD API but is not endorsed or certified by the NVD.