ALPINE-CVE-2026-66046
Expat through 2.8.3 contains a denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function in xmlparse.c, where processing N specified attributes with non-normalized values triggers an O(N^2) linear scan of elementType->defaultAtts to determine CDATA status. A remote unauthenticated attacker can supply a single well-formed XML document of a few megabytes to an application parsing untrusted XML to cause excessive CPU consumption, resulting in denial of service without requiring authentication, external entity resolution, or non-default parser options.
ALPINE-CVE-2026-66046
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:ALPINE-CVE-2026-66046
expat
Source reference: /affected/0/package/name
- Affected versions
- Not stated in this record
- Fixed versions
- 2.8.4-r0
Source reference:
/affected/0/ranges - Prerequisites
- Not stated in this record
expat
Source reference: /affected/1/package/name
- Affected versions
- Not stated in this record
- Fixed versions
- 2.8.4-r0
Source reference:
/affected/1/ranges - Prerequisites
- Not stated in this record
expat
Source reference: /affected/2/package/name
- Affected versions
- Not stated in this record
- Fixed versions
- 2.8.4-r0
Source reference:
/affected/2/ranges - Prerequisites
- Not stated in this record
expat
Source reference: /affected/3/package/name
- Affected versions
- Not stated in this record
- Fixed versions
- 2.8.4-r0
Source reference:
/affected/3/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": "2.8.4-r0"
}
]
}
],
"package": {
"name": "expat",
"purl": "pkg:apk/alpine/expat?arch=source",
"ecosystem": "Alpine:v3.21"
},
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-66046.json"
},
"ecosystem_specific": {}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.8.4-r0"
}
]
}
],
"package": {
"name": "expat",
"purl": "pkg:apk/alpine/expat?arch=source",
"ecosystem": "Alpine:v3.22"
},
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-66046.json"
},
"ecosystem_specific": {}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.8.4-r0"
}
]
}
],
"package": {
"name": "expat",
"purl": "pkg:apk/alpine/expat?arch=source",
"ecosystem": "Alpine:v3.23"
},
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-66046.json"
},
"ecosystem_specific": {}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.8.4-r0"
}
]
}
],
"package": {
"name": "expat",
"purl": "pkg:apk/alpine/expat?arch=source",
"ecosystem": "Alpine:v3.24"
},
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-66046.json"
},
"ecosystem_specific": {}
}
]Publisher severity
No explicit severity was provided.
- Event
- #54632 · Revision 1
- Added to Heist Feed
- Publisher date