CVE-2025-2123 — geshi
CVE-2025-2123 is a Cross-site Scripting (XSS) vulnerability in geshi/geshi. The records list no fixed version yet; check the vendor advisory below and apply the mitigations in the meantime.
GeSHi CSS cssgen.php get_var cross site scripting
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-2123.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
Real-World Exposure
geshi/geshiReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
A vulnerability, which was classified as problematic, has been found in GeSHi up to 1.0.9.1. Affected by this issue is the function get_var of the file /contrib/cssgen.php of the component CSS Handler. The manipulation of the argument default-styles/keywords-1/keywords-2/keywords-3/keywords-4/comments leads to cross site scripting. The attack may be launched remotely. The exploit has been disclosed to the public and may be used.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | geshi/geshi | all versions | No fix |
Affected Products
geshiqbnzDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for geshi/geshi, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
The records we use list no patched version of geshi/geshi for CVE-2025-2123. Check the maintainer's advisory, and where your build allows, override or pin the dependency away from the vulnerable range.
Mitigate without a patch
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.
Frequently Asked Questions
Is CVE-2025-2123 in your dependencies?
Find it across Packagist, including transitive dependencies.