CVE-2023-4575

When creating a callback over IPC for showing the File Picker window, multiple of the same callbacks could have been created at a time and eventually all simultaneously destroyed as soon as one of the callbacks finished. This could have led to a use-after-free causing a potentially exploitable crash. This vulnerability affects Firefox < 117, Firefox ESR < 102.15, Firefox ESR < 115.2, Thunderbird < 102.15, and Thunderbird < 115.2.

Weakness

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.

Affected Software

Potential Mitigations

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=1846689
• https://www.mozilla.org/security/advisories/mfsa2023-34/
• https://www.mozilla.org/security/advisories/mfsa2023-35/
• https://www.mozilla.org/security/advisories/mfsa2023-36/
• https://www.mozilla.org/security/advisories/mfsa2023-37/
• https://www.mozilla.org/security/advisories/mfsa2023-38/
• https://bugzilla.mozilla.org/show_bug.cgi?id=1846689
• https://www.mozilla.org/security/advisories/mfsa2023-34/
• https://www.mozilla.org/security/advisories/mfsa2023-35/
• https://www.mozilla.org/security/advisories/mfsa2023-36/
• https://www.mozilla.org/security/advisories/mfsa2023-37/
• https://www.mozilla.org/security/advisories/mfsa2023-38/