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.
Affected products
mozilla: firefox; mozilla: thunderbird
References9
- www.mozilla.org/security/advisories/mfsa2025-56/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-57/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-58/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-59/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-61/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-62/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-63/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=1968423 Permissions Required
- lists.debian.org/debian-lts-announce/2025/07/msg00016.html
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 38 · as of 8 November 2026
- CWE
- CWE-457
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