Low severity · published Jun 23, 2026
CVE-2026-55654
Openssh: heap out-of-bounds read in red hat enterprise linux versions of openssh gssapi indicator cleanup due to missing null sentinel termination
3.7
CVSS
0.7%
EPSS
No
On KEV
Description
A flaw was found in OpenSSH. This vulnerability, a heap out-of-bounds read, occurs during the cleanup of GSSAPI (Generic Security Service Application Programming Interface) indicators when a trailing NULL termination is missing in the auth-indicators array. A remote attacker, under specific configurations involving GSSAPI authentication and a Kerberos environment, could exploit this to cause the SSH authentication path to crash or abort. This leads to a denial of service (DoS), impacting the availability of the SSH service.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 51% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RH
Red Hat Enterprise Linux 10 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 9 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Hardened Images · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat OpenShift Container Platform 4 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Update Infrastructure 5 · Red Hat
All versions, or not specified · source: vendor
EL
Enterprise Linux · Redhat
6.0; 7.0; 8.0; 9.0; 10.0 · source: NVD
HI
Hardened Images · Redhat
All versions, or not specified · source: NVD
OP
Openssh · Openbsd
All versions, or not specified · source: NVD
Affected product
RH
Red Hat Enterprise Linux 10
Red Hat
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