CVE-2025-10148

Summary

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.

Impact & exploitability

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Affected products we track (1)

Recommendation

Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.

Official patch: https://curl.se/docs/CVE-2025-10148.html ↗

Additional information

• NVD record
• https://curl.se/docs/CVE-2025-10148.htmlPatch
• http://www.openwall.com/lists/oss-security/2025/09/10/2Patch
• https://curl.se/docs/CVE-2025-10148.jsonAdvisory
• https://hackerone.com/reports/3330839Advisory
• http://www.openwall.com/lists/oss-security/2025/09/10/3Advisory
• http://www.openwall.com/lists/oss-security/2025/09/10/4Advisory