CVE
CVE-2026-19931
Negotiate ambient user conn reuse
A flaw in libcurl makes it wrongly reuse an HTTP connection setup for a given
hostname using Negotiate authentication, when the initial request is done
using empty credentials. This can make user B's request get sent over user A's
previously authenticated connection.
Package Versions Affected
Package Version
patch Availability
No items found.
Automatically patch vulnerabilities without upgrading
Fix Without Upgrading
Detect compatible fix
Apply safe remediation
Fix with a single pull request
CVSS Version
Severity
Base Score
CVSS Version
Score Vector
C
H
U
9.8
-
3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
C
H
U
0
-
3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
C
H
U
-
Related Resources
No items found.
References
https://curl.se/docs/CVE-2026-19931.html, https://curl.se/docs/CVE-2026-19931.json, https://hackerone.com/reports/3923520, https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/19xxx/CVE-2026-19931.json, https://nvd.nist.gov/vuln/detail/CVE-2026-19931, https://github.com/curl/curl.git