DEBIAN-CVE-2026-4867
Impact: A bad regular expression is generated any time you have three or more parameters within a single segment, separated by something that is not a period (.). For example, /:a-:b-:c or /:a-:b-:c-:d. The backtrack protection added in path-to-regexp@0.1.12 only prevents ambiguity for two parameters. With three or more, the generated lookahead does not block single separator characters, so capture groups overlap and cause catastrophic backtracking. Patches: Upgrade to path-to-regexp@0.1.13 Custom regex patterns in route definitions (e.g., /:a-:b([^-/]+)-:c([^-/]+)) are not affected because they override the default capture group. Workarounds: All versions can be patched by providing a custom regular expression for parameters after the first in a single segment. As long as the custom regular expression does not match the text before the parameter, you will be safe. For example, change /:a-:b-:c to /:a-:b([^-/]+)-:c([^-/]+). If paths cannot be rewritten and versions cannot be upgraded, another alternative is to limit the URL length.
DEBIAN-CVE-2026-4867
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:DEBIAN-CVE-2026-4867
node-path-to-regexp
Source reference: /affected/0/package/name
- Affected versions
- Not stated in this record
- Fixed versions
- 1.0.1-1
Source reference:
/affected/0/ranges - Prerequisites
- Not stated in this record
node-path-to-regexp
Source reference: /affected/1/package/name
- Affected versions
- Not stated in this record
- Fixed versions
- 1.0.1-1
Source reference:
/affected/1/ranges - Prerequisites
- Not stated in this record
node-path-to-regexp
Source reference: /affected/2/package/name
- Affected versions
- Not stated in this record
- Fixed versions
- 1.0.1-1
Source reference:
/affected/2/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.0.1-1"
}
]
}
],
"package": {
"name": "node-path-to-regexp",
"purl": "pkg:deb/debian/node-path-to-regexp?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-4867.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.0.1-1"
}
]
}
],
"package": {
"name": "node-path-to-regexp",
"purl": "pkg:deb/debian/node-path-to-regexp?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-4867.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.0.1-1"
}
]
}
],
"package": {
"name": "node-path-to-regexp",
"purl": "pkg:deb/debian/node-path-to-regexp?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-4867.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #57238 · Revision 1
- Added to Heist Feed
- Publisher date