nginx: Fix of CVE-2026-56434
- CVE-2026-56434: fix use-after-free in ngx_http_ssi_filter_module from duplicate subrequest finalization; ngx_http_post_request() now skips posting a request that is already queued, and ngx_http_finalize_request() resets r->write_event_handler to a no-op handler during active subrequest finalization
- Products
- nginx, nginx-all-modules, nginx-core, nginx-filesystem, nginx-mod-devel, nginx-mod-http-image-filter, nginx-mod-http-perl, nginx-mod-http-xslt-filter, nginx-mod-mail, nginx-mod-stream
- Affected versions
- Not specified
- Fixed versions
- 1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14
- CVEs
- CVE-2026-56434
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 10:44 UTC · Revision 1
Source evidence
- CVE-2026-56434: fix use-after-free in ngx_http_ssi_filter_module from duplicate subrequest finalization; ngx_http_post_request() now skips posting a request that is already queued, and ngx_http_finalize_request() resets r->write_event_handler to a no-op handler during active subrequest finalization
osv:CLSA-2026-1787916225
nginx
Fixed versions: 1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14
nginx-all-modules
Fixed versions: 1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14
nginx-core
Fixed versions: 1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14
nginx-filesystem
Fixed versions: 1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14
nginx-mod-devel
Fixed versions: 1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14
nginx-mod-http-image-filter
Fixed versions: 1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14
nginx-mod-http-perl
Fixed versions: 1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14
nginx-mod-http-xslt-filter
Fixed versions: 1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14
nginx-mod-mail
Fixed versions: 1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14
nginx-mod-stream
Fixed versions: 1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14
Complete source record
{
"id": "ff41622686364239595803c0e2eddd7734b1ed7fec0d2e780799a61712ea69c1",
"url": "https://osv.dev/vulnerability/CLSA-2026-1787916225",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "nginx: Fix of CVE-2026-56434",
"summary": "- CVE-2026-56434: fix use-after-free in ngx_http_ssi_filter_module from duplicate subrequest finalization; ngx_http_post_request() now skips posting a request that is already queued, and ngx_http_finalize_request() resets r->write_event_handler to a no-op handler during active subrequest finalization",
"evidence": "osv:CLSA-2026-1787916225",
"products": [
{
"name": {
"value": "nginx",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
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"evidence": "/affected/1/package/name"
},
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"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
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"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
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],
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{
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},
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"evidence": "/affected/3/ranges"
}
],
"affected_versions": []
},
{
"name": {
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"evidence": "/affected/4/package/name"
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],
"affected_versions": []
},
{
"name": {
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"evidence": "/affected/5/package/name"
},
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{
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"evidence": "/affected/5/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "nginx-mod-http-perl",
"evidence": "/affected/6/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14",
"evidence": "/affected/6/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "nginx-mod-http-xslt-filter",
"evidence": "/affected/7/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14",
"evidence": "/affected/7/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "nginx-mod-mail",
"evidence": "/affected/8/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14",
"evidence": "/affected/8/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "nginx-mod-stream",
"evidence": "/affected/9/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14",
"evidence": "/affected/9/ranges"
}
],
"affected_versions": []
}
],
"severity": "unknown",
"structured": {
"id": "CLSA-2026-1787916225",
"aliases": [
"CLSA-2026-1787916225"
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14"
}
]
}
],
"package": {
"name": "nginx",
"purl": "pkg:rpm/tuxcare/nginx?distro=almalinux-9.2",
"ecosystem": "TuxCare:AlmaLinux:9.2"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.2esu/CLSA-2026-1787916225.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
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"introduced": "0"
},
{
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}
]
}
],
"package": {
"name": "nginx-all-modules",
"purl": "pkg:rpm/tuxcare/nginx-all-modules?distro=almalinux-9.2",
"ecosystem": "TuxCare:AlmaLinux:9.2"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.2esu/CLSA-2026-1787916225.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14"
}
]
}
],
"package": {
"name": "nginx-core",
"purl": "pkg:rpm/tuxcare/nginx-core?distro=almalinux-9.2",
"ecosystem": "TuxCare:AlmaLinux:9.2"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.2esu/CLSA-2026-1787916225.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14"
}
]
}
],
"package": {
"name": "nginx-filesystem",
"purl": "pkg:rpm/tuxcare/nginx-filesystem?distro=almalinux-9.2",
"ecosystem": "TuxCare:AlmaLinux:9.2"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.2esu/CLSA-2026-1787916225.json"
}
},
{
"ranges": [
{
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{
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}
]
}
],
"package": {
"name": "nginx-mod-devel",
"purl": "pkg:rpm/tuxcare/nginx-mod-devel?distro=almalinux-9.2",
"ecosystem": "TuxCare:AlmaLinux:9.2"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.2esu/CLSA-2026-1787916225.json"
}
},
{
"ranges": [
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],
"package": {
"name": "nginx-mod-http-image-filter",
"purl": "pkg:rpm/tuxcare/nginx-mod-http-image-filter?distro=almalinux-9.2",
"ecosystem": "TuxCare:AlmaLinux:9.2"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.2esu/CLSA-2026-1787916225.json"
}
},
{
"ranges": [
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}
]
}
],
"package": {
"name": "nginx-mod-http-perl",
"purl": "pkg:rpm/tuxcare/nginx-mod-http-perl?distro=almalinux-9.2",
"ecosystem": "TuxCare:AlmaLinux:9.2"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.2esu/CLSA-2026-1787916225.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14"
}
]
}
],
"package": {
"name": "nginx-mod-http-xslt-filter",
"purl": "pkg:rpm/tuxcare/nginx-mod-http-xslt-filter?distro=almalinux-9.2",
"ecosystem": "TuxCare:AlmaLinux:9.2"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.2esu/CLSA-2026-1787916225.json"
}
},
{
"ranges": [
{
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},
{
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}
]
}
],
"package": {
"name": "nginx-mod-mail",
"purl": "pkg:rpm/tuxcare/nginx-mod-mail?distro=almalinux-9.2",
"ecosystem": "TuxCare:AlmaLinux:9.2"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.2esu/CLSA-2026-1787916225.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
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{
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},
{
"fixed": "1:1.20.1-14.el9_2.1.alma.1.tuxcare.els14"
}
]
}
],
"package": {
"name": "nginx-mod-stream",
"purl": "pkg:rpm/tuxcare/nginx-mod-stream?distro=almalinux-9.2",
"ecosystem": "TuxCare:AlmaLinux:9.2"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/almalinux9.2esu/CLSA-2026-1787916225.json"
}
}
],
"modified": "2026-10-26T09:30:37.239766572Z",
"provider": "osv",
"upstream": [
"CVE-2026-56434"
],
"references": [
"https://errata.tuxcare.com/els_os/almalinux9.2esu/CLSA-2026-1787916225.html",
"https://nvd.nist.gov/vuln/detail/CVE-2026-56434"
]
},
"related_cves": [
{
"value": "CVE-2026-56434",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 447167,
"published_at": "2026-08-28T11:23:56+00:00"
}