CVE-2026-117920: Use-after-free in the DOM: HTML Parser component
Vulnerability summary
CVE-2026-117920 is a vulnerability in thunderbird with no CVSS score yet. EPSS estimates a 0.18% chance of exploitation in the next 30 days, higher than 7.7% of scored vulnerabilities.
No CVSS vector published; no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 3 · Related 3Timeline
- 27-10-2026PublishedVulnerability first disclosed.
- 27-10-2026Last modifiedVulnerability information updated.
Description
Use-after-free in the DOM: HTML Parser component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
CVSS metrics
Risk metrics not yet published.
EPSS trend
Probability
0.18%
Chance of exploitation in the next 30 days
Percentile
8%
Versus all other CVEs
30-day change
Change unavailable
Change unavailable
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Known conditions: not stated in public data.
Ubuntu8 products
- mozjs102All versions (No fix recorded)
- mozjs115All versions (No fix recorded)
- mozjs38All versions (No fix recorded)
- mozjs52All versions (No fix recorded)
- mozjs68All versions (No fix recorded)
Debian2 products
- firefox-esrAll versions (No fix recorded) | < 153.6.0esr-1~deb12u2 | < 153.6.0esr-1~deb13u1
- thunderbirdAll versions (No fix recorded) | < 1:153.6.0esr-1~deb12u2 | < 1:153.6.0esr-1~deb13u1
2 vendors · 10 products
