Description
`NSC_DeriveKey` inadvertently assumed that the `phKey` parameter is always non-NULL. When it was passed as NULL, a segmentation fault (SEGV) occurred, leading to crashes. This behavior conflicted with the PKCS#11 v3.0 specification, which allows `phKey` to be NULL for certain mechanisms. This vulnerability affects Firefox < 133 and Thunderbird < 133.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mozilla | Firefox | unspecified – < 133 | 133 |
| Mozilla | Thunderbird | unspecified – < 133 | 133 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | mozjs102 +1 | No fix yet | — |
| Ubuntu 22.04 LTS | mozjs78 +2 | No fix yet | — |
| Ubuntu 20.04 LTS | firefox | 133.0+build2-0ubuntu0.20.04.1 | USN-7134-1 |
| Ubuntu 20.04 LTS | mozjs52 +1 | No fix yet | — |
| Ubuntu 18.04 LTS | mozjs38 +1 | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | MozillaFirefox | 133.0.3-1.1 | openSUSE-SU-2024:14583-1 |
| openSUSE Tumbleweed | firefox-esr | 153.0-1.1 | openSUSE-SU-2026:11373-1 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | firefox | 133.0-r0 | — |
Advisories 4
- openSUSE-SU-2026:11373-1 firefox-esr-153.0-1.1 on GA media SUSE / openSUSE Security Updates · Jul 26, 2026
- WID-SEC-2024-3549 Mozilla Firefox und Thunderbird: Mehrere Schwachstellen BSI CERT-Bund (WID) · May 31, 2026
- USN-7134-1 firefox vulnerabilities Ubuntu Security Notices (USN) · Apr 27, 2026
- openSUSE-SU-2024:14583-1 MozillaFirefox-133.0.3-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026