CVE-2026-110249: Vulnerability in Mozilla Thunderbird
Description
CVE-2026-110249 is a vulnerability in Mozilla Thunderbird where a malicious or compromised Exchange server can send a SOAP response designed to keep Thunderbird's main thread CPU-bound for an extended period. This can cause significant performance degradation. The issue was fixed in Thunderbird versions 158 and 153.5.
Affected software
Mozilla
Thunderbird
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a malicious, compromised, or man-in-the-middle controlled Exchange server returning a single well-formed SOAP response containing an element with enough attributes to cause Thunderbird's main thread to remain CPU-bound for seconds to hours. This denial-of-service condition affects the responsiveness and performance of Thunderbird. The vulnerability has been addressed and fixed in Thunderbird versions 158 and 153.5.
Potential Impact
The impact is a denial-of-service condition where Thunderbird's main thread can be kept busy processing a crafted SOAP response, leading to significant CPU consumption and degraded application responsiveness for potentially extended periods. There is no indication of data compromise or remote code execution from the provided information.
Mitigation Recommendations
This vulnerability has been fixed in Thunderbird versions 158 and 153.5. Users should upgrade to these versions or later to remediate the issue. No additional mitigation actions are indicated by the vendor advisories.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T18:08:37.893Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-109/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-110/","vendor":"Mozilla"}]
Threat ID: 6ace79b72cdf04f656972473
Added to database: 10/13/2026, 18:34:31 UTC
Last enriched: 10/13/2026, 18:50:16 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 7
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