CVE-2026-110249

high

Description

A malicious, compromised, or MITM-controlled Exchange server can return a single well-formed SOAP response containing an element with enough attributes to keep Thunderbird's main thread CPU-bound for seconds to hours. This vulnerability was fixed in Thunderbird 158 and Thunderbird 153.5.

References

https://www.mozilla.org/security/advisories/mfsa2026-110/

https://www.mozilla.org/security/advisories/mfsa2026-109/

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-99208

https://bugzilla.mozilla.org/show_bug.cgi?id=2077826

Details

Source: Mitre, NVD

Published: 2026-10-13

Updated: 2026-10-20

Risk Information

CVSS v2

Base Score: 7.2

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C

Severity: High

CVSS v3

Base Score: 8.6

Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

Severity: High

EPSS

EPSS: 0.0018