caddy — security advisory
Caddy is an extensible server platform that uses TLS by default. From 2.7.0 until 2.11.3, the FastCGI transport's splitPos() in modules/caddyhttp/reverseproxy/fastcgi/fastcgi.go misuses golang.org/x/text/search with search.IgnoreCase when the request path contains a non-ASCII byte. Two distinct flaws in that fallback let an attacker mislead Caddy's FastCGI splitting into treating a non-.php (or other configured split_path extension) file as a script. In any deployment where the attacker can place content into a file served via FastCGI (uploads, file storage, etc.), this can be escalated to remote code execution by crafting a URL whose path triggers either flaw. This vulnerability is fixed in 2.11.3.
- Products
- caddy
- Affected versions
- 2.11.4-1, 2.6.2-11, 2.6.2-12, 2.6.2-14, 2.6.2-14ubuntu0.26.04.1~esm1, 2.6.2-6, 2.6.2-6ubuntu0.24.04.1, 2.6.2-6ubuntu0.24.04.2, 2.6.2-6ubuntu0.24.04.2+esm1, 2.6.2-6ubuntu0.24.04.3, 2.6.2-6ubuntu0.24.04.3+esm1, 2.6.2-6ubuntu0.24.04.3+esm2, 2.6.2-9
- Fixed versions
- Not specified
- CVEs
- CVE-2026-45135
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 03:05 UTC · Revision 1
Source evidence
Caddy is an extensible server platform that uses TLS by default. From 2.7.0 until 2.11.3, the FastCGI transport's splitPos() in modules/caddyhttp/reverseproxy/fastcgi/fastcgi.go misuses golang.org/x/text/search with search.IgnoreCase when the request path contains a non-ASCII byte. Two distinct flaws in that fallback let an attacker mislead Caddy's FastCGI splitting into treating a non-.php (or other configured split_path extension) file as a script. In any deployment where the attacker can place content into a file served via FastCGI (uploads, file storage, etc.), this can be escalated to remote code execution by crafting a URL whose path triggers either flaw. This vulnerability is fixed in 2.11.3.
osv:UBUNTU-CVE-2026-45135
caddy
Fixed versions: Not specified
caddy
Fixed versions: Not specified
caddy
Fixed versions: Not specified
caddy
Fixed versions: Not specified
Complete source record
{
"id": "99fd6edfe1abd8cc09962f62c54de76087125c0cadb72303e28ea75fe3479b6d",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-45135",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-45135",
"summary": "Caddy is an extensible server platform that uses TLS by default. From 2.7.0 until 2.11.3, the FastCGI transport's splitPos() in modules/caddyhttp/reverseproxy/fastcgi/fastcgi.go misuses golang.org/x/text/search with search.IgnoreCase when the request path contains a non-ASCII byte. Two distinct flaws in that fallback let an attacker mislead Caddy's FastCGI splitting into treating a non-.php (or other configured split_path extension) file as a script. In any deployment where the attacker can place content into a file served via FastCGI (uploads, file storage, etc.), this can be escalated to remote code execution by crafting a URL whose path triggers either flaw. This vulnerability is fixed in 2.11.3.",
"evidence": "osv:UBUNTU-CVE-2026-45135",
"products": [
{
"name": {
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"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.6.2-6",
"evidence": "/affected/0/versions"
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{
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"evidence": "/affected/0/versions"
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{
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{
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"evidence": "/affected/0/versions"
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{
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{
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{
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{
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{
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{
"name": {
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},
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"affected_versions": [
{
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"evidence": "/affected/3/versions"
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{
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},
{
"value": "2.6.2-14ubuntu0.26.04.1~esm1",
"evidence": "/affected/3/versions"
}
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}
],
"severity": "high",
"structured": {
"id": "UBUNTU-CVE-2026-45135",
"aliases": [
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],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"
},
{
"type": "Ubuntu",
"score": "medium"
}
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"affected": [
{
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"events": [
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"package": {
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"ecosystem": "Ubuntu:Pro:24.04:LTS"
},
"versions": [
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"2.6.2-6ubuntu0.24.04.3",
"2.6.2-6ubuntu0.24.04.3+esm1",
"2.6.2-6ubuntu0.24.04.3+esm2"
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"database_specific": {
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"versions": [
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"package": {
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"ecosystem": "Ubuntu:26.10"
},
"versions": [
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"2.11.4-1"
],
"database_specific": {
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},
"ecosystem_specific": {
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{
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"binary_version": "2.11.4-1"
}
]
}
},
{
"ranges": [
{
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],
"package": {
"name": "caddy",
"purl": "pkg:deb/ubuntu/caddy?arch=source&distro=esm-apps%2Fresolute",
"ecosystem": "Ubuntu:Pro:26.04:LTS"
},
"versions": [
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"2.6.2-14",
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}
],
"modified": "2026-10-17T13:00:11.119144644Z",
"provider": "osv",
"upstream": [
"CVE-2026-45135"
],
"references": [
"https://ubuntu.com/security/CVE-2026-45135",
"https://www.cve.org/CVERecord?id=CVE-2026-45135"
]
},
"related_cves": [
{
"value": "CVE-2026-45135",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 360385,
"published_at": "2026-06-23T18:17:00+00:00"
}