CVE catalog
CVE-2021-36773
ublock-origin: CVE-2021-36773
- Severity
- Medium
- Published
- Source
- [NVD] · [CVE record]
- EPSS
- 1.26% · Oct 25, 2026
uBlock Origin before 1.36.2 and nMatrix before 4.4.9 support an arbitrary depth of parameter nesting for strict blocking, which allows crafted web sites to cause a denial of service (unbounded recursion that can trigger memory consumption and a loss of all blocking functionality).
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | ublock-origin | sid | 1.67.0+dfsg-1 | fixed |
| Debian | ublock-origin | forky | 1.67.0+dfsg-1 | fixed |
| Debian | ublock-origin | trixie | 1.67.0+dfsg-1~deb13u1 | fixed |
| Debian | ublock-origin | bookworm | 1.67.0+dfsg-1~deb12u1 | fixed |
| Ubuntu | ublock-origin | 16.04 | 1.5.6+dfsg-1 | vulnerable |
| Ubuntu | ublock-origin | 16.04 | 1.6.0+dfsg-1 | vulnerable |
| Ubuntu | ublock-origin | 16.04 | 1.6.6+dfsg-1 | vulnerable |
| Ubuntu | ublock-origin | 18.04 | 1.13.8+dfsg-1 | vulnerable |
| Ubuntu | ublock-origin | 20.04 | 1.19.0+dfsg-2 | vulnerable |
| Ubuntu | ublock-origin | 20.04 | 1.22.2+dfsg-1 | vulnerable |
| Ubuntu | umatrix | 20.04 | 1.3.16+dfsg-2 | vulnerable |
| Ubuntu | ublock-origin | 22.04 | 1.33.0+dfsg-1build1 | vulnerable |
| Ubuntu | ublock-origin | 22.04 | 1.37.0+dfsg-1 | vulnerable |
| Ubuntu | ublock-origin | 22.04 | 1.39.0+dfsg-2 | vulnerable |
| Ubuntu | ublock-origin | 22.04 | 1.40.2+dfsg-1 | vulnerable |
| Ubuntu | umatrix | 22.04 | 1.4.0+dfsg-1 | vulnerable |
| Ubuntu | ublock-origin | 24.04 | 1.51.0+dfsg-2 | vulnerable |
| Ubuntu | ublock-origin | 24.04 | 1.52.0+dfsg-1 | vulnerable |
| Ubuntu | ublock-origin | 24.04 | 1.53.3rc0+dfsg-1 | vulnerable |
| Ubuntu | ublock-origin | 24.04 | 1.54.0+dfsg-1 | vulnerable |
| Ubuntu | ublock-origin | 24.04 | 1.55.0+dfsg-1 | vulnerable |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | ublock-origin | source | sid | 1.37.0+dfsg-1 | not yet assigned | Not reported | [991386] |
| Debian | ublock-origin | source | forky | 1.37.0+dfsg-1 | not yet assigned | Not reported | [991386] |
| Debian | ublock-origin | source | trixie | 1.37.0+dfsg-1 | not yet assigned | Not reported | [991386] |
| Debian | ublock-origin | source | bookworm | 1.37.0+dfsg-1 | not yet assigned | Not reported | [991386] |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [ublock-origin-doc]Fixed
Source package: [ublock-origin]
Details (2)
1.67.0+dfsg-1~deb12u1· all · bookwormFixed · Fixed:
1.37.0+dfsg-1dsa · ublock-origin · debian · bookworm; dsa · ublock-origin · debian · 12
1.67.0+dfsg-1~deb12u1· all · bookwormFixed · Fixed:
1.37.0+dfsg-1dsa · ublock-origin · debian · bookworm; dsa · ublock-origin · debian · 12
Source package: [ublock-origin]
Details (2)
1.67.0+dfsg-1~deb12u1· all · bookwormFixed · Fixed:
1.37.0+dfsg-1dsa · ublock-origin · debian · bookworm; dsa · ublock-origin · debian · 12
1.67.0+dfsg-1~deb12u1· all · bookwormFixed · Fixed:
1.37.0+dfsg-1dsa · ublock-origin · debian · bookworm; dsa · ublock-origin · debian · 12
- [webext-ublock-origin-firefox]Fixed
Source package: [ublock-origin]
Details (2)
1.67.0+dfsg-1~deb12u1· all · bookwormFixed · Fixed:
1.37.0+dfsg-1dsa · ublock-origin · debian · bookworm; dsa · ublock-origin · debian · 12
1.67.0+dfsg-1~deb12u1· all · bookwormFixed · Fixed:
1.37.0+dfsg-1dsa · ublock-origin · debian · bookworm; dsa · ublock-origin · debian · 12
[Debian 13 (Trixie)]
- [ublock-origin-doc]Fixed
Source package: [ublock-origin]
Details (2)
1.67.0+dfsg-1~deb13u1· all · trixieFixed · Fixed:
1.37.0+dfsg-1dsa · ublock-origin · debian · 13
1.67.0+dfsg-1~deb13u1· all · trixieFixed · Fixed:
1.37.0+dfsg-1dsa · ublock-origin · debian · 13
Source package: [ublock-origin]
Details (2)
1.67.0+dfsg-1~deb13u1· all · trixieFixed · Fixed:
1.37.0+dfsg-1dsa · ublock-origin · debian · 13
1.67.0+dfsg-1~deb13u1· all · trixieFixed · Fixed:
1.37.0+dfsg-1dsa · ublock-origin · debian · 13
- [webext-ublock-origin-firefox]Fixed
Source package: [ublock-origin]
Details (2)
1.67.0+dfsg-1~deb13u1· all · trixieFixed · Fixed:
1.37.0+dfsg-1dsa · ublock-origin · debian · 13
1.67.0+dfsg-1~deb13u1· all · trixieFixed · Fixed:
1.37.0+dfsg-1dsa · ublock-origin · debian · 13
Observed: