CVE-2026-8956: Vulnerability in Mozilla Firefox
Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
AI Analysis
Technical Summary
This vulnerability involves an integer overflow in the Networking: JAR component of Mozilla Firefox. Integer overflow bugs can lead to unexpected behavior, potentially causing memory corruption or other security issues. Mozilla fixed this vulnerability in Firefox 151 and Firefox ESR 140.11. The advisory categorizes the impact as moderate and does not report any active exploitation. The fix is included in the official Firefox and Firefox ESR updates.
Potential Impact
The vulnerability could potentially allow an attacker to cause unintended behavior in the Networking: JAR component due to integer overflow. Mozilla rates the impact as moderate, indicating a security concern that could affect confidentiality, integrity, or availability but without evidence of active exploitation or critical severity. No known exploits in the wild have been reported.
Mitigation Recommendations
Mozilla has officially fixed this vulnerability in Firefox 151 and Firefox ESR 140.11. Users should update their Firefox installations to these versions or later to remediate this issue. Since the vulnerability is patched, no additional mitigation steps are required beyond applying the official update.
CVE-2026-8956: Vulnerability in Mozilla Firefox
Description
Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves an integer overflow in the Networking: JAR component of Mozilla Firefox. Integer overflow bugs can lead to unexpected behavior, potentially causing memory corruption or other security issues. Mozilla fixed this vulnerability in Firefox 151 and Firefox ESR 140.11. The advisory categorizes the impact as moderate and does not report any active exploitation. The fix is included in the official Firefox and Firefox ESR updates.
Potential Impact
The vulnerability could potentially allow an attacker to cause unintended behavior in the Networking: JAR component due to integer overflow. Mozilla rates the impact as moderate, indicating a security concern that could affect confidentiality, integrity, or availability but without evidence of active exploitation or critical severity. No known exploits in the wild have been reported.
Mitigation Recommendations
Mozilla has officially fixed this vulnerability in Firefox 151 and Firefox ESR 140.11. Users should update their Firefox installations to these versions or later to remediate this issue. Since the vulnerability is patched, no additional mitigation steps are required beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-05-19T12:29:50.365Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-46/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-48/","vendor":"Mozilla"}]
Threat ID: 6a0c677bec166c07b0a993e0
Added to database: 5/19/2026, 1:36:59 PM
Last enriched: 5/19/2026, 1:55:03 PM
Last updated: 5/20/2026, 7:51:49 PM
Views: 9
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