Low
openssh, openssh-ssh1 — security advisory
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.
- Products
- openssh, openssh-ssh1
- Affected versions
- 1:10.0p1-5ubuntu2, 1:10.0p1-5ubuntu3, 1:10.0p1-5ubuntu4, 1:10.0p1-5ubuntu5, 1:10.0p1-5ubuntu5.1, 1:10.0p1-5ubuntu5.4, 1:7.5p1-10, 1:7.5p1-11build1, 1:7.5p1-12, 1:7.5p1-12build1, 1:7.5p1-13, 1:7.5p1-14, 1:7.5p1-15, 1:7.5p1-15build1, 1:7.5p1-16, 1:7.5p1-17, 1:7.5p1-18, 1:7.5p1-18ubuntu1, 1:7.5p1-18ubuntu2, 1:7.5p1-8, 1:7.5p1-9, 1:7.5p1-9build1, 1:9.9p1-3ubuntu3, 1:9.9p1-3ubuntu3.1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-55654
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 02:46 UTC · Revision 1
Source evidence
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.
osv:UBUNTU-CVE-2026-55654
openssh-ssh1
Fixed versions: Not specified
openssh-ssh1
Fixed versions: Not specified
openssh-ssh1
Fixed versions: Not specified
openssh-ssh1
Fixed versions: Not specified
openssh
Fixed versions: Not specified
openssh-ssh1
Fixed versions: Not specified
openssh-ssh1
Fixed versions: Not specified
openssh-ssh1
Fixed versions: Not specified
Complete source record
{
"id": "a798739ef0c2e551402388d28aea7b7e4e1ef49388cfbdd7c69def1a3e061986",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-55654",
"method": "structured",
"payload": {
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"title": "UBUNTU-CVE-2026-55654",
"summary": "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.",
"evidence": "osv:UBUNTU-CVE-2026-55654",
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],
"modified": "2026-10-17T12:59:07.935118612Z",
"provider": "osv",
"upstream": [
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"references": [
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"https://access.redhat.com/security/cve/CVE-2026-55654"
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"source_id": "core-osv",
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"published_at": "2026-06-23T04:17:00+00:00"
}