CVE-2025-4215: A vulnerability was found in gorhill uBlock Origin up to 1.63.3b16

Q: How do I fix CVE-2025-4215?

ublock origin: upgrade to 1.63.3; debian linux: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Q: Is CVE-2025-4215 being exploited?

CVE-2025-4215 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2025-4215 affect?

CVE-2025-4215 affects ublock origin, debian linux. Severity is low (CVSS 3.1). A vulnerability was found in gorhill uBlock Origin up to 1.63.3b16. It has been classified as problematic. Affected is the function currentStateChanged of the file src/js/1p-filters.js of the component UI. The manipulation leads to ineffici

Q: How urgent is CVE-2025-4215?

Priority 35/100. Public exploit reference; On your watchlist

Routine

LOW 3.1WATCHLISTUPGRADEMITIGATE

CVE-2025-4215 is a low-severity flaw (CVSS 3.1) affecting ublock origin, debian linux. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A vulnerability was found in gorhill uBlock Origin up to 1.63.3b16. It has been classified as problematic. Affected is the function currentStateChanged of the file src/js/1p-filters.js of the component UI. The manipulation leads to inefficient regular expression complexity. It is possible to launch the attack remotely. The complexity of an attack is rather high. The exploitability is told to be difficult. The exploit has been disclosed to the pub

Why this priority

Public exploit reference
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	3.1 (Low)
Attack vector	Network (remote)
Attack complexity	High
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.8% (top 44%)
CISA exploited list	No
Weakness	CWE-400, CWE-1333
Published	2025-05-02
Last modified	2026-06-17

Publisher (CNA): VulDB · Vendor: debian · ublockorigin

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2025-05-02 21:15 UTCPublished CVE record published
2026-06-17 09:32 UTCUpdated Record last modified

ublockorigin ublock origin UPGRADE

Affected: < 1.63.3 · 1.63.3 beta1 · 1.63.3 beta10 · 1.63.3 beta11 · 1.63.3 beta12 · 1.63.3 beta13 · 1.63.3 beta14 · 1.63.3 beta15

Fixed in: 1.63.3

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy ublock-origin || rpm -q ublock-origin || ublock-origin --version

2. UPGRADE to 1.63.3 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade ublock-origin

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade ublock-origin

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

debian debian linux MITIGATE

Affected: 11.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 11.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2025-4215?

ublock origin: upgrade to 1.63.3; debian linux: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2025-4215 being exploited?

CVE-2025-4215 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2025-4215 affect?

CVE-2025-4215 affects ublock origin, debian linux. Severity is low (CVSS 3.1). A vulnerability was found in gorhill uBlock Origin up to 1.63.3b16. It has been classified as problematic. Affected is the function currentStateChanged of the file src/js/1p-filters.js of the component UI. The manipulation leads to ineffici

How urgent is CVE-2025-4215?

Priority 35/100. Public exploit reference; On your watchlist

Software pages

Debian vulnerabilities

References

← Back to latest CVEs