What is CVE-2026-12437?
Use after free in WebShare in Google Chrome on Windows prior to 149.0.7827.155 allowed a remote attacker who had compromised the renderer process to potentially perform a sandbox escape via a crafted HTML page. (Chromium security severity: Critical)
The record classifies CVE-2026-12437 under weakness class CWE-416. 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 133 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 8.3 — HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H - EPSS (FIRST)
- 0.2% probability of exploitation in the next 30 days, higher than 19.4% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 4.9/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-06-17, last modified 2026-06-18
Is CVE-2026-12437 being exploited?
No public exploitation evidence for CVE-2026-12437 is recorded in the sources Threadlinqs tracks — CISA KEV, Exploit-DB, public proof-of-concept repositories and ProjectDiscovery Nuclei — as of 2026-06-18. That is an absence of evidence in those feeds, not a guarantee that the vulnerability is unexploited.
Affected products and versions
- Google: Chrome
How to fix CVE-2026-12437
No vendor patch reference has been recorded for CVE-2026-12437 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2026-12437
1 tracked threat in the Threadlinqs corpus references CVE-2026-12437, either in the campaign’s CVE list or as an indicator on the campaign record.
Sources
Enriched from CVE.org, FIRST EPSS, GitHub Security Advisories. Last verified by Threadlinqs on .