How severe is CVE-2023-50251?

CVE-2023-50251 has a CVSS score of 5.3/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2023-50251?

CVE-2023-50251 affects the following packages: phenx/php-svg-lib (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2023-50251?

Update phenx/php-svg-lib to 0.5.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-50251 is resolved across your whole dependency graph.

How do I detect CVE-2023-50251 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for phenx/php-svg-lib. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2023-50251 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2023-50251?

O3 pinpoints whether CVE-2023-50251 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2023-50251 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2023-50251, including 1 in-the-wild exploitation observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2023-50251?

CVE-2023-50251 has an EPSS (Exploit Prediction Scoring System) score of 0.9%, placing it in the 54th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

When was CVE-2023-50251 published, and has it been updated?

CVE-2023-50251 was published on December 12, 2023 and was last updated on April 2, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘 Packagist

CVE-2023-50251

MEDIUM

php-svg-lib possible DoS caused by infinite recursion when parsing SVG document

Also known asGHSA-ff5x-7qg5-vwf2

Published

Dec 12, 2023

Updated

Apr 2, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

1 known

EPSS Exploitation Probability

via FIRST.org ↗

0.9%probability of exploitation in next 30 days

Lower Risk54th percentile+0.61%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

1 pkg affected

🐘phenx/php-svg-lib

Real-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

php-svg-lib is an SVG file parsing / rendering library. Prior to version 0.5.1, when parsing the attributes passed to a use tag inside an svg document, an attacker can cause the system to go to an infinite recursion. Depending on the system configuration and attack pattern this could exhaust the memory available to the executing process and/or to the server itself. An attacker sending multiple request to a system to render the above payload can potentially cause resource exhaustion to the point that the system is unable to handle incoming request. Version 0.5.1 contains a patch for this issue.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`phenx/php-svg-lib`	all versions	0.5.1

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

php-svg-lib is an SVG file parsing / rendering library. Prior to version…

github.comNVDDec 2023

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for phenx/php-svg-lib. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update phenx/php-svg-lib to 0.5.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-50251 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2023-50251 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2023-50251. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

php-svg-lib is an SVG file parsing / rendering library. Prior to version 0.5.1, when parsing the attributes passed to a `use` tag inside an svg document, an attacker can cause the system to go to an infinite recursion. Depending on the system configuration and attack pattern this could exhaust the memory available to the executing process and/or to the server itself. An attacker sending multiple request to a system to render the above payload can potentially cause resource exhaustion to the point that the system is unable to handle incoming request. Version 0.5.1 contains a patch for this issu

O3 Security · Impact-Aware SCA

Is CVE-2023-50251 in your dependencies?

O3 detects CVE-2023-50251 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works