What is CVE-2024-21623?

CVE-2024-21623 is a critical-severity vulnerability in Mehah Otclient, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 9.8/10. Published 2024-01-02.

How severe is CVE-2024-21623?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2024-21623 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Mehah Otclient

CVE-2024-21623

OTCLient is an alternative tibia client for otserv. Prior to commit db560de0b56476c87a2f967466407939196dd254, the /mehah/otclient "`Analysis - SonarCloud`" workflow is vulnerable to an expression injection in Actions, allowing an attacker to run commands remotely on the runner, leak secrets, and alter the repository using this workflow. Commit db560de0b56476c87a2f967466407939196dd254 contains a fix for this issue.

Published 2024-01-02 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.012 (68.0th percentile), scored 2026-10-02.

Low probability of exploitation in the next 30 days, but still tracked. 68th percentile — 68.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.012 · newest: 0.012 · change: 0.000

Affected products

Mehah Otclient — versions < db560de0b56476c87a2f967466407939196dd254

Weakness classification (CWE)

CWE-74 — Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection)

Public proof-of-concept exploits

References

github.com/mehah/otclient/security/advisories/GHSA-q6gr-wc79-v589 (Exploit, Vendor Advisory)
github.com/mehah/otclient/commit/db560de0b56476c87a2f967466407939196dd254 (Patch)
github.com/mehah/otclient/blob/72744edc3b9913b920e0fd12e929604f682fda75/.github… (Product)
securitylab.github.com/research/github-actions-preventing-pwn-requests/ (Exploit, Third Party Advisory)
securitylab.github.com/research/github-actions-untrusted-input/ (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2024-21623?: CVE-2024-21623 is a critical-severity vulnerability in Mehah Otclient, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 9.8/10. Published 2024-01-02.
How severe is CVE-2024-21623?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2024-21623 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.