CVE-2025-5399 - CVE House
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Status published Unknown CVE-2025-5399

WebSocket endless loop

Vulnerability Description

Due to a mistake in libcurl's WebSocket code, a malicious server can send a particularly crafted packet which makes libcurl get trapped in an endless busy-loop. There is no other way for the application to escape or exit this loop other than killing the thread/process. This might be used to DoS libcurl-using application.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • z2_ on hackerone
  • z2_ on hackerone

References

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Affected Vendor

Affected Software

curl
Vulnerable Versions:
8.14.0, 8.13.0

Timeline

Official Publish: June 7th, 2025
Last Modified: June 9th, 2025
Added to House: July 22nd, 2026

CVSS Vectors

No vector data available

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.