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: 2026-10-13

Risk Information

CVSS v2

Base Score: 4.3

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

Severity: Medium

CVSS v3

Base Score: 7.5

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

Severity: High

EPSS

EPSS: 0.00171