CVE-2019-3856

critical
Published — · Modified —
CVSS v3
CVSS v2
VIR risk
9.5

Description

An integer overflow flaw, which could lead to an out of bounds write, was discovered in libssh2 before 1.8.1 in the way keyboard prompt requests are parsed. A remote attacker who compromises a SSH server may be able to execute code on the client system when a user connects to the server.

Predictions

Exploit likelihood
20%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2019-3856

vendor Authored 2026-05-27

Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2019-3856.html

vendor Authored 2026-05-27

Vendor advisory: arch — https://security.archlinux.org/ASA-201903-12

OS impact

OSVersionStatusFixed in
arch archfixed1.8.1-1
suse slesaffected
debian debianbookwormfixed1.8.0-2.1
debian debianbullseyefixed1.8.0-2.1
debian debianforkyfixed1.8.0-2.1
debian debiansidfixed1.8.0-2.1
debian debiantrixiefixed1.8.0-2.1

References

Verify integrity in audit chain (admin only). AS-IS.