Vulnary
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Critical· 9.3

CVE-2021-47936

OpenCATS 0.9.4 has a critical remote code execution flaw that lets anyone upload a PHP file disguised as a resume and run arbitrary commands on the server. The vulnerability is exploitable without authentication and can be triggered through the careers job application endpoint.

publishedMay 10, 2026
last modifiedJul 25, 2026
sourcesNVD
severity · cvss
9.3
critical · how bad it is
exploitation · epss
<1%
48th percentile · chance of exploitation in 30 days
(ai-assisted) A model wrote this summary from the official data, so double-check it against the source before you act on it. Read the official advisory →
auto-deletes from the system
counting…on Sep 7, 2026

No official fix yet. If none appears within 45 days of first tracking, this entry is removed automatically.

01

Who is affected

OpenCATS 0.9.4 – the open‑source applicant tracking system.

02

Real-world impact

An attacker can upload a malicious PHP file, then send a request to that file to execute any command on the server, potentially taking full control of the system.

03

Why this severity

The CVSS score of 9.3 reflects the combination of remote exploitation, lack of authentication, and the ability to execute arbitrary code with high impact on confidentiality, integrity, and availability.

04

What to do about it

no official fix yet

No official fix or mitigation is documented in the sources yet. Monitor the vendor advisory and apply the patch as soon as it is released.

No fix documented in sources

05

Timeline

  1. May 10, 2026 · May 10, 2026
    Published
    Disclosed and added to the National Vulnerability Database.
  2. Jul 25, 2026 · 11d ago
    Advisory updated
    The NVD record was last revised.
06

How it’s attacked

Attack vectorNetwork (remote)
Attack complexityLow
Attack requirementsNone
Privileges requiredNone
User interactionNone needed
Confidentiality impactHigh
Integrity impactHigh
Availability impactHigh
07

References & advisories

(ai-assisted) A model wrote this summary from the official data, so double-check it against the source before you act on it. Read the official advisory →