Vulnerability Description
On 64-bit platforms IonMonkey-JIT only wrote 32 bits of the 64-bit return value space on the stack. Baseline-JIT, however, read the entire 64 bits. This vulnerability was fixed in Firefox 141, Firefox ESR 115.26, Firefox ESR 128.13, Firefox ESR 140.1, Thunderbird 141, Thunderbird 128.13, and Thunderbird 140.1.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Firefox | < 115.26.0 |
| Mozilla | Thunderbird | < 128.13.0 |
Related Weaknesses (CWE)
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1968423Permissions Required
- https://www.mozilla.org/security/advisories/mfsa2025-56/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-57/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-58/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-59/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-61/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-62/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-63/Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2025/07/msg00016.html
FAQ
What is CVE-2025-8027?
CVE-2025-8027 is a vulnerability with a CVSS score of 6.5 (MEDIUM). On 64-bit platforms IonMonkey-JIT only wrote 32 bits of the 64-bit return value space on the stack. Baseline-JIT, however, read the entire 64 bits. This vulnerability was fixed in Firefox 141, Firefox...
How severe is CVE-2025-8027?
CVE-2025-8027 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-8027?
Check the references section above for vendor advisories and patch information. Affected products include: Mozilla Firefox, Mozilla Thunderbird.