| Name | CVE-2021-23960 |
| Description | Performing garbage collection on re-declared JavaScript variables resulted in a user-after-poison, and a potentially exploitable crash. This vulnerability affects Firefox < 85, Thunderbird < 78.7, and Firefox ESR < 78.7. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, GitHub code/issues, web search, more) |
| References | DLA-2539-1, DLA-2541-1, DSA-4840-1, DSA-4842-1 |
| NVD severity | medium |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| firefox (PTS) | sid | 93.0-1 | fixed |
| firefox-esr (PTS) | stretch | 68.10.0esr-1~deb9u1 | vulnerable |
| stretch (security) | 78.15.0esr-1~deb9u1 | fixed | |
| buster | 78.14.0esr-1~deb10u1 | fixed | |
| buster (security) | 78.15.0esr-1~deb10u1 | fixed | |
| bullseye | 78.14.0esr-1~deb11u1 | fixed | |
| bullseye (security) | 78.15.0esr-1~deb11u1 | fixed | |
| bookworm | 78.14.0esr-1 | fixed | |
| sid | 91.2.0esr-1 | fixed | |
| thunderbird (PTS) | stretch | 1:68.10.0-1~deb9u1 | vulnerable |
| stretch (security) | 1:78.14.0-1~deb9u1 | fixed | |
| buster, buster (security) | 1:78.14.0-1~deb10u1 | fixed | |
| bullseye (security), bullseye | 1:78.14.0-1~deb11u1 | fixed | |
| bookworm, sid | 1:78.14.0-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| firefox | source | (unstable) | 85.0-1 | |||
| firefox-esr | source | stretch | 78.7.0esr-1~deb9u1 | DLA-2539-1 | ||
| firefox-esr | source | buster | 78.7.0esr-1~deb10u1 | DSA-4840-1 | ||
| firefox-esr | source | (unstable) | 78.7.0esr-1 | |||
| thunderbird | source | stretch | 1:78.7.0-1~deb9u1 | DLA-2541-1 | ||
| thunderbird | source | buster | 1:78.7.0-1~deb10u1 | DSA-4842-1 | ||
| thunderbird | source | (unstable) | 1:78.7.0-1 |
https://www.mozilla.org/en-US/security/advisories/mfsa2021-04/#CVE-2021-23960
https://www.mozilla.org/en-US/security/advisories/mfsa2021-03/#CVE-2021-23960
https://www.mozilla.org/en-US/security/advisories/mfsa2021-05/#CVE-2021-23960