CVE-2026-5773

high

Description

libcurl might in some circumstances reuse the wrong connection for SMB(S) transfers. libcurl features a pool of recent connections so that subsequent requests can reuse an existing connection to avoid overhead. When reusing a connection a range of criteria must be met. Due to a logical error in the code, a network transfer operation that was requested by an application could wrongfully reuse an existing SMB connection to the same server that was using a different 'share' than the new subsequent transfer should. This could in unlucky situations lead to the download of the wrong file or the upload of a file to the wrong place. When this happens, the same credentials are used and the server name is the same.

References

https://hackerone.com/reports/3650689

https://curl.se/docs/CVE-2026-5773.json

https://curl.se/docs/CVE-2026-5773.html

http://www.openwall.com/lists/oss-security/2026/04/29/9

Details

Source: Mitre, NVD

Published: 2026-05-13

Updated: 2026-05-13

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:N/A:N

Severity: High

CVSS v3

Base Score: 7.5

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

Severity: High

EPSS

EPSS: 0.00018