CVE-2025-8033

The JavaScript engine did not handle closed generators correctly and it was possible to resume them leading to a nullptr deref. 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 3.1

6.5CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

EPSS

0.4% chance of exploitation in the next 30 days; higher than 37% of CVEs (scores of 2026-10-25)

CWE

CWE-476

Published

2025-07-22

Modified

2026-10-05

Record from

the NVD, synced 2026-10-19

Affected

• mozilla:firefox
• mozilla:thunderbird

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=1973990
• https://www.mozilla.org/security/advisories/mfsa2025-56/
• https://www.mozilla.org/security/advisories/mfsa2025-57/
• https://www.mozilla.org/security/advisories/mfsa2025-58/
• https://www.mozilla.org/security/advisories/mfsa2025-59/

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