High severity · published May 1, 2026
CVE-2026-7598
libssh2 userauth.c userauth_password integer overflow
7.3
CVSS
0.5%
EPSS
No
On KEV
Description
A security vulnerability has been detected in libssh2 up to 1.11.1. The impacted element is the function userauth_password of the file src/userauth.c. Such manipulation of the argument username_len/password_len leads to integer overflow. The attack may be launched remotely. The name of the patch is 256d04b60d80bf1190e96b0ad1e91b2174d744b1. A patch should be applied to remediate this issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
libssh2 · Libssh2
1.11.0; 1.11.1 · source: vendor, NVD
RH
Red Hat Enterprise Linux 6 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 7 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Hardened Images · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Trusted Profile Analyzer · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-7598
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-7598
Product
https://github.com/libssh2/libssh2/
Patch
https://github.com/libssh2/libssh2/commit/256d04b60d80bf1190e96b0ad1e91b2174d744b1
Issue Tracking
https://github.com/libssh2/libssh2/pull/1858
Third Party Advisory
https://vuldb.com/submit/805564
Third Party Advisory
https://vuldb.com/vuln/360555
Permissions Required
https://vuldb.com/vuln/360555/cti
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