openssh: Fix of CVE-2026-55655
- CVE-2026-55655: gate the client-side abstract X11 socket behind SSH_INSECURE_ABSTRACT_SOCKET_ENABLED to prevent MITM of forwarded X11 via abstract UNIX socket pre-binding; backport downstream f5884eb
- Products
- openssh, openssh-askpass, openssh-clients, openssh-keycat, openssh-server, openssh-sk-dummy, pam_ssh_agent_auth
- Affected versions
- Not specified
- Fixed versions
- 0.10.4-5.45.el9_6.tuxcare.els15, 8.7p1-45.el9_6.tuxcare.els15
- CVEs
- CVE-2026-55655
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 10:52 UTC · Revision 1
Source evidence
- CVE-2026-55655: gate the client-side abstract X11 socket behind SSH_INSECURE_ABSTRACT_SOCKET_ENABLED to prevent MITM of forwarded X11 via abstract UNIX socket pre-binding; backport downstream f5884eb
osv:CLSA-2026-1785143860
openssh
Fixed versions: 8.7p1-45.el9_6.tuxcare.els15
openssh-askpass
Fixed versions: 8.7p1-45.el9_6.tuxcare.els15
openssh-clients
Fixed versions: 8.7p1-45.el9_6.tuxcare.els15
openssh-keycat
Fixed versions: 8.7p1-45.el9_6.tuxcare.els15
openssh-server
Fixed versions: 8.7p1-45.el9_6.tuxcare.els15
openssh-sk-dummy
Fixed versions: 8.7p1-45.el9_6.tuxcare.els15
pam_ssh_agent_auth
Fixed versions: 0.10.4-5.45.el9_6.tuxcare.els15
Complete source record
{
"id": "8f4d0ef0058a8e304dc2961a6e95518e86799911f36d99706a3d9a2b003af159",
"url": "https://osv.dev/vulnerability/CLSA-2026-1785143860",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "openssh: Fix of CVE-2026-55655",
"summary": "- CVE-2026-55655: gate the client-side abstract X11 socket behind SSH_INSECURE_ABSTRACT_SOCKET_ENABLED to prevent MITM of forwarded X11 via abstract UNIX socket pre-binding; backport downstream f5884eb",
"evidence": "osv:CLSA-2026-1785143860",
"products": [
{
"name": {
"value": "openssh",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "8.7p1-45.el9_6.tuxcare.els15",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "openssh-askpass",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "8.7p1-45.el9_6.tuxcare.els15",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "openssh-clients",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "8.7p1-45.el9_6.tuxcare.els15",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "openssh-keycat",
"evidence": "/affected/3/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "8.7p1-45.el9_6.tuxcare.els15",
"evidence": "/affected/3/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "openssh-server",
"evidence": "/affected/4/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "8.7p1-45.el9_6.tuxcare.els15",
"evidence": "/affected/4/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "openssh-sk-dummy",
"evidence": "/affected/5/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "8.7p1-45.el9_6.tuxcare.els15",
"evidence": "/affected/5/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "pam_ssh_agent_auth",
"evidence": "/affected/6/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "0.10.4-5.45.el9_6.tuxcare.els15",
"evidence": "/affected/6/ranges"
}
],
"affected_versions": []
}
],
"severity": "unknown",
"structured": {
"id": "CLSA-2026-1785143860",
"aliases": [
"CLSA-2026-1785143860"
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "8.7p1-45.el9_6.tuxcare.els15"
}
]
}
],
"package": {
"name": "openssh",
"purl": "pkg:rpm/tuxcare/openssh?distro=almalinux-9.6",
"ecosystem": "TuxCare:AlmaLinux:9.6"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.6esu/CLSA-2026-1785143860.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "8.7p1-45.el9_6.tuxcare.els15"
}
]
}
],
"package": {
"name": "openssh-askpass",
"purl": "pkg:rpm/tuxcare/openssh-askpass?distro=almalinux-9.6",
"ecosystem": "TuxCare:AlmaLinux:9.6"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.6esu/CLSA-2026-1785143860.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "8.7p1-45.el9_6.tuxcare.els15"
}
]
}
],
"package": {
"name": "openssh-clients",
"purl": "pkg:rpm/tuxcare/openssh-clients?distro=almalinux-9.6",
"ecosystem": "TuxCare:AlmaLinux:9.6"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.6esu/CLSA-2026-1785143860.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "8.7p1-45.el9_6.tuxcare.els15"
}
]
}
],
"package": {
"name": "openssh-keycat",
"purl": "pkg:rpm/tuxcare/openssh-keycat?distro=almalinux-9.6",
"ecosystem": "TuxCare:AlmaLinux:9.6"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.6esu/CLSA-2026-1785143860.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "8.7p1-45.el9_6.tuxcare.els15"
}
]
}
],
"package": {
"name": "openssh-server",
"purl": "pkg:rpm/tuxcare/openssh-server?distro=almalinux-9.6",
"ecosystem": "TuxCare:AlmaLinux:9.6"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.6esu/CLSA-2026-1785143860.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "8.7p1-45.el9_6.tuxcare.els15"
}
]
}
],
"package": {
"name": "openssh-sk-dummy",
"purl": "pkg:rpm/tuxcare/openssh-sk-dummy?distro=almalinux-9.6",
"ecosystem": "TuxCare:AlmaLinux:9.6"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.6esu/CLSA-2026-1785143860.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.10.4-5.45.el9_6.tuxcare.els15"
}
]
}
],
"package": {
"name": "pam_ssh_agent_auth",
"purl": "pkg:rpm/tuxcare/pam_ssh_agent_auth?distro=almalinux-9.6",
"ecosystem": "TuxCare:AlmaLinux:9.6"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.6esu/CLSA-2026-1785143860.json"
}
}
],
"modified": "2026-10-26T09:31:23.833908413Z",
"provider": "osv",
"upstream": [
"CVE-2026-55655"
],
"references": [
"https://errata.tuxcare.com/els_os/tuxcare9.6esu/CLSA-2026-1785143860.html",
"https://nvd.nist.gov/vuln/detail/CVE-2026-55655"
]
},
"related_cves": [
{
"value": "CVE-2026-55655",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 447637,
"published_at": "2026-07-27T09:17:51+00:00"
}