Description
Using iterative requests an attacker was able to learn the size of an opaque response, as well as the contents of a server-supplied Vary header. This vulnerability affects Firefox < 119.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mozilla | Firefox | unspecified – < 119 | 119 |
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 | No fix yet | — |
| Ubuntu 22.04 LTS | mozjs78 +2 | No fix yet | — |
| Ubuntu 20.04 LTS | firefox | 119.0+build2-0ubuntu0.20.04.1 | USN-6456-1 |
| Ubuntu 20.04 LTS | mozjs52 +1 | No fix yet | — |
| Ubuntu 18.04 LTS | mozjs38 +1 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP5 | MozillaFirefox | 115.4.0-150200.152.114.1 | SUSE-SU-2023:4214-1 |
| SLES 15 SP4 | MozillaFirefox | 115.4.0-150200.152.114.1 | SUSE-SU-2023:4214-1 |
| SLES 15 SP3 | MozillaFirefox | 115.4.0-150200.152.114.1 | SUSE-SU-2023:4214-1 |
| SLES 15 SP2 | MozillaFirefox | 115.4.0-150200.152.114.1 | SUSE-SU-2023:4214-1 |
| SLES 15 SP1 | MozillaFirefox | 115.4.0-150000.150.113.1 | SUSE-SU-2023:4213-1 |
Show 9 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP5 | MozillaFirefox | 115.4.0-112.188.1 | SUSE-SU-2023:4212-1 |
| SLES for SAP 15 SP3 | MozillaFirefox | 115.4.0-150200.152.114.1 | SUSE-SU-2023:4214-1 |
| SLES for SAP 15 SP2 | MozillaFirefox | 115.4.0-150200.152.114.1 | SUSE-SU-2023:4214-1 |
| SLES for SAP 15 SP1 | MozillaFirefox | 115.4.0-150000.150.113.1 | SUSE-SU-2023:4213-1 |
| SLES for SAP 12 SP5 | MozillaFirefox | 115.4.0-112.188.1 | SUSE-SU-2023:4212-1 |
| SLE HPC 15 SP3 | MozillaFirefox | 115.4.0-150200.152.114.1 | SUSE-SU-2023:4214-1 |
| SLE HPC 15 SP2 | MozillaFirefox | 115.4.0-150200.152.114.1 | SUSE-SU-2023:4214-1 |
| SLE HPC 15 SP1 | MozillaFirefox | 115.4.0-150000.150.113.1 | SUSE-SU-2023:4213-1 |
| SUSE Enterprise Storage 7.1 | MozillaFirefox | 115.4.0-150200.152.114.1 | SUSE-SU-2023:4214-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | MozillaFirefox | 119.0-1.1 | openSUSE-SU-2024:13385-1 |
| openSUSE Tumbleweed | firefox-esr | 128.5.1-1.1 | openSUSE-SU-2024:14572-1 |
| openSUSE Leap 15.5 | MozillaFirefox | 115.4.0-150200.152.114.1 | SUSE-SU-2023:4214-1 |
| openSUSE Leap 15.4 | MozillaFirefox | 115.4.0-150200.152.114.1 | SUSE-SU-2023:4214-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | librewolf | 119.0-r0 | — |
| Alpine v3.23 | firefox +1 | 119.0-r0 | — |
| Alpine v3.22 | firefox +1 | 119.0-r0 | — |
| Alpine v3.21 | firefox | 119.0-r0 | — |
| Alpine v3.20 | firefox | 119.0-r0 | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | firefox | 119.0-r0 | — |
| Alpine v3.18 | firefox | 119.0-r0 | — |
Advisories 7
- USN-6456-1 firefox vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- SUSE-SU-2023:4214-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:4212-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:13385-1 MozillaFirefox-119.0-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:4213-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:14572-1 firefox-esr-128.5.1-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2023-2743 Mozilla Firefox und Thunderbird: Mehrere Schwachstellen BSI CERT-Bund (WID) · Dec 15, 2024