All vulnerabilities
CVE-2026-113869

Thunderbird: Use-after-free in S/MIME decryption during a security device password prompt

Mozilla Thunderbird
Open in ThreatlineRecord JSON
CVSS
5.4Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.28%Chance of exploitation activity in the next 30 days, higher than 19% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed inNone listedNo source names a fixed version. Check the vendor advisory below
Published20 Oct 2026Updated 20 Oct 2026CVE List

What fixes it

No source in this snapshot names a fixed version. The vendor advisories under References are the place to check.

Description

When Thunderbird asked for a security device password (for example a smartcard PIN or the Primary Password) while decrypting an S/MIME message, the message load could finish or be cancelled while the prompt was open. This freed the message decoder while it was still in use, causing a use-after-free and a potentially exploitable crash. This vulnerability was fixed in Thunderbird 158.0.1.

Text from CVE List

Affected versions 1

  • Thunderbirdunaffected: 158.0.1CVE List

References 2