CVE-2025-8043 Incorrect URL truncation
Critical 9.8
Published
Updated
Check this codebase for CVE-2025-8043 and fix it if it is affected.
What it is: CVE-2025-8043 is a critical vulnerability in Mozilla Firefox, published on 22 Jul 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-8043 in the wild and no public exploit code.
Affected product: Mozilla Firefox. No package-level version data is available, so check the vendor advisory linked from the reference page.
Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.
Reference: https://insights.sbomify.com/CVE-2025-8043/ (Markdown: https://insights.sbomify.com/CVE-2025-8043/index.md)
Incorrect URL truncation in Firefox could allow attackers to spoof origins, bypassing security checks related to URL display.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-8043?
CVE-2025-8043 is a critical vulnerability in Mozilla Firefox, published on 22 Jul 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Focus incorrectly truncated URLs towards the beginning instead of around the origin. This vulnerability was fixed in Firefox 141.
Weakness: CWE-451
Which versions are affected by CVE-2025-8043?
It affects 2 products.
Products include Mozilla Firefox, Mozilla Thunderbird.
How do I fix CVE-2025-8043?
Upgrade to a fixed version.
Is CVE-2025-8043 being exploited?
There is no known exploitation of CVE-2025-8043 in the wild and no public exploit code.
Other vulnerabilities in Mozilla Firefox
Sources
Also known as GHSA-ww6j-fhx6-wrxh, UBUNTU-CVE-2025-8043.