CVE-2025-10148: curl's websocket code did not update the 32 bit mask pattern for each new outgoing frame as the
Source GCVE Database
Not known to be exploited · CVSS 5.3 Medium.
Data as of 13 Nov 2026, 18:29 UTC
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:NExploitation evidence
Disclosed: evidence found.
CVE published 12 Sep 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
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.
References
- nvd.nist.gov/vuln/detail/CVE-2025-10148 (opens in a new tab)
- hackerone.com/reports/3330839 (opens in a new tab)
- curl.se/docs/CVE-2025-10148.html (opens in a new tab)
- curl.se/docs/CVE-2025-10148.json (opens in a new tab)
- openwall.com/lists/oss-security/2025/09/10/2 (opens in a new tab)
- openwall.com/lists/oss-security/2025/09/10/3 (opens in a new tab)
- openwall.com/lists/oss-security/2025/09/10/4 (opens in a new tab)