Analyzed
Published: 12 Sept 2025, 05:10
Last modified:18 Nov 2025, 20:05

Vulnerability Summary

Overall Risk (default)
low
21/100
CVSS Score
5.3 MEDIUM
v3.1 (cve.org)
EPSS Score
0.47% LOW
0% probability +0.37%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

12 Sept 2025, 05:10
Published
Vulnerability first disclosed
18 Nov 2025, 20:05
Last Modified
Vulnerability information updated

Description

curl's websocket code did not update the 32 bit mask pattern for each new outgoing frame as the specification says. Instead it used a fixed mask that persisted and was used throughout the entire connection. A predictable mask pattern allows for a malicious server to induce traffic between the two communicating parties that could be interpreted by an involved proxy (configured or transparent) as genuine, real, HTTP traffic with content and thereby poison its cache. That cached poisoned content could then be served to all users of that proxy.

CVSS Metrics

  • v3.1MEDIUMScore: 5.3CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS Trends

Current EPSS score: 0.47% Percentile: 37%

Affected Systems

  • curlcurl

    8.15.0 | 8.14.1 | 8.14.0 | 8.13.0 | 8.12.1 | 8.12.0 | 8.11.1 | 8.11.0

  • haxxcurl

    ≥ 8.11.0, < 8.16.0

References (6)