CVE-2025-26465

EUVD-2025-4686
A vulnerability was found in OpenSSH when the VerifyHostKeyDNS option is enabled. A machine-in-the-middle attack can be performed by a malicious machine impersonating a legit server. This issue occurs due to how OpenSSH mishandles error codes in specific conditions when verifying the host key. For an attack to be considered successful, the attacker needs to manage to exhaust the client's memory resource first, turning the attack complexity high.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
6.8 MEDIUM
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
Base Score
CVSS 3.x
EPSS Score
Percentile: 98%
Affected Products (NVD)
VendorProductVersion
openbsdopenssh
6.9 ≤
𝑥
≤ 9.8
openbsdopenssh
6.8:p1
openbsdopenssh
9.9
openbsdopenssh
9.9:p1
netappactive_iq_unified_manager
-
redhatopenshift_container_platform
4.0
debiandebian_linux
11.0
debiandebian_linux
12.0
redhatenterprise_linux
9.0
𝑥
= Vulnerable software versions
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
SiemensSIMATIC S7-1500 CPU 1518-4 PN\/DP MFP
V3.1.5 ≤
𝑥
< *
ADP
SiemensSIMATIC S7-1500 CPU 1518-4 PN\/DP MFP
V3.1.5 ≤
𝑥
< *
ADP
SiemensSIMATIC S7-1500 CPU 1518F-4 PN\/DP MFP
V3.1.5 ≤
𝑥
< *
ADP
SiemensSIMATIC S7-1500 CPU 1518F-4 PN\/DP MFP
V3.1.5 ≤
𝑥
< *
ADP
SiemensSIPLUS S7-1500 CPU 1518-4 PN\/DP MFP
V3.1.5 ≤
𝑥
< *
ADP
Debian logo
Debian Releases
Debian Product
Codename
openssh
bookworm
1:9.2p1-2+deb12u10
fixed
bookworm (security)
1:9.2p1-2+deb12u9
fixed
bullseye
vulnerable
bullseye (security)
1:8.4p1-5+deb11u7
fixed
forky
1:10.3p1-2
fixed
sid
1:10.3p1-4
fixed
trixie
1:10.0p1-7+deb13u4
fixed
trixie (security)
1:10.0p1-7+deb13u2
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
openssh
bionic
Fixed 1:7.6p1-4ubuntu0.7+esm4
released
focal
Fixed 1:8.2p1-4ubuntu0.12
released
jammy
Fixed 1:8.9p1-3ubuntu0.11
released
noble
Fixed 1:9.6p1-3ubuntu13.8
released
oracular
Fixed 1:9.7p1-7ubuntu4.2
released
plucky
Fixed 9.9p1-3ubuntu3
released
questing
Fixed 9.9p1-3ubuntu3
released
resolute
Fixed 9.9p1-3ubuntu3
released
trusty
not-affected
xenial
Fixed 1:7.2p2-4ubuntu2.10+esm7
released
openssh-ssh1
bionic
ignored
focal
ignored
jammy
ignored
noble
ignored
oracular
ignored
plucky
ignored
questing
ignored
resolute
ignored
Red Hat logo
Red Hat Enterprise Linux Releases
Red Hat Product
Release
openssh
RHEL 8
0:8.0p1-26.el8_10
fixed
RHEL 9
0:8.7p1-45.el9
fixed
openssh-askpass
RHEL 8
0:8.0p1-26.el8_10
fixed
RHEL 9
0:8.7p1-45.el9
fixed
openssh-cavs
RHEL 8
0:8.0p1-26.el8_10
fixed
openssh-clients
RHEL 8
0:8.0p1-26.el8_10
fixed
RHEL 9
0:8.7p1-45.el9
fixed
openssh-keycat
RHEL 8
0:8.0p1-26.el8_10
fixed
RHEL 9
0:8.7p1-45.el9
fixed
openssh-ldap
RHEL 8
0:8.0p1-26.el8_10
fixed
openssh-server
RHEL 8
0:8.0p1-26.el8_10
fixed
RHEL 9
0:8.7p1-45.el9
fixed
pam
RHEL 8
0:0.10.3-7.26.el8_10
fixed
RHEL 9
0:0.10.4-5.45.el9
fixed
References