mongoose — security advisory
Mongoose is an embedded web server and network library. Prior to 7.22, an attacker who can create a file with an HTML payload in its name can trigger stored cross-site scripting when a user browses a directory served with MG_ENABLE_DIRLIST. The printdirentry() path called by listdir() in src/http.c URL-encodes the href but inserts the raw filesystem filename into the HTML link text. The browser executes the injected markup in the Mongoose origin, which can expose session data or permit actions as the victim. This issue is fixed in version 7.22.
- Products
- mongoose
- Affected versions
- 7.21+ds-1, 7.21+ds-2, 7.22+ds-1, 7.23+ds-1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-73254
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 03:15 UTC · Revision 1
Source evidence
Mongoose is an embedded web server and network library. Prior to 7.22, an attacker who can create a file with an HTML payload in its name can trigger stored cross-site scripting when a user browses a directory served with MG_ENABLE_DIRLIST. The printdirentry() path called by listdir() in src/http.c URL-encodes the href but inserts the raw filesystem filename into the HTML link text. The browser executes the injected markup in the Mongoose origin, which can expose session data or permit actions as the victim. This issue is fixed in version 7.22.
osv:UBUNTU-CVE-2026-73254
mongoose
Fixed versions: Not specified
Complete source record
{
"id": "8b028acf60a4fb7cf07365b5219fff42f620a9cbe9a7e5b76a1ab347d2baf1eb",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-73254",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-73254",
"summary": "Mongoose is an embedded web server and network library. Prior to 7.22, an attacker who can create a file with an HTML payload in its name can trigger stored cross-site scripting when a user browses a directory served with MG_ENABLE_DIRLIST. The printdirentry() path called by listdir() in src/http.c URL-encodes the href but inserts the raw filesystem filename into the HTML link text. The browser executes the injected markup in the Mongoose origin, which can expose session data or permit actions as the victim. This issue is fixed in version 7.22.",
"evidence": "osv:UBUNTU-CVE-2026-73254",
"products": [
{
"name": {
"value": "mongoose",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "7.21+ds-1",
"evidence": "/affected/0/versions"
},
{
"value": "7.21+ds-2",
"evidence": "/affected/0/versions"
},
{
"value": "7.22+ds-1",
"evidence": "/affected/0/versions"
},
{
"value": "7.23+ds-1",
"evidence": "/affected/0/versions"
}
]
}
],
"severity": "medium",
"structured": {
"id": "UBUNTU-CVE-2026-73254",
"aliases": [
"UBUNTU-CVE-2026-73254"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N"
},
{
"type": "Ubuntu",
"score": "medium"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "mongoose",
"purl": "pkg:deb/ubuntu/mongoose?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
},
"versions": [
"7.21+ds-1",
"7.21+ds-2",
"7.22+ds-1",
"7.23+ds-1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-73254.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "mongoose-webserver-source",
"binary_version": "7.23+ds-1"
}
]
}
}
],
"modified": "2026-10-17T13:01:02.774318983Z",
"provider": "osv",
"upstream": [
"CVE-2026-73254"
],
"references": [
"https://ubuntu.com/security/CVE-2026-73254",
"https://www.cve.org/CVERecord?id=CVE-2026-73254"
]
},
"related_cves": [
{
"value": "CVE-2026-73254",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 360898,
"published_at": "2026-08-20T18:16:00+00:00"
}