MediumFix available
libxml2 — security advisory
A vulnerability found in libxml2 in versions before 2.9.11 shows that it did not propagate errors while parsing XML mixed content, causing a NULL dereference. If an untrusted XML document was parsed in recovery mode and post-validated, the flaw could be used to crash the application. The highest threat from this vulnerability is to system availability.
- Products
- libxml2
- Affected versions
- Not specified
- Fixed versions
- 2.9.10-r5, 2.9.10-r6, 2.9.10-r7, 2.9.11-r0, 2.9.9-r5
- CVEs
- CVE-2021-3537
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 22:05 UTC · Revision 1
Source evidence
A vulnerability found in libxml2 in versions before 2.9.11 shows that it did not propagate errors while parsing XML mixed content, causing a NULL dereference. If an untrusted XML document was parsed in recovery mode and post-validated, the flaw could be used to crash the application. The highest threat from this vulnerability is to system availability.
osv:ALPINE-CVE-2021-3537
libxml2
Fixed versions: 2.9.9-r5
libxml2
Fixed versions: 2.9.10-r5
libxml2
Fixed versions: 2.9.10-r6
libxml2
Fixed versions: 2.9.10-r7
libxml2
Fixed versions: 2.9.11-r0
libxml2
Fixed versions: 2.9.11-r0
libxml2
Fixed versions: 2.9.11-r0
libxml2
Fixed versions: 2.9.11-r0
libxml2
Fixed versions: 2.9.11-r0
libxml2
Fixed versions: 2.9.11-r0
libxml2
Fixed versions: 2.9.11-r0
libxml2
Fixed versions: 2.9.11-r0
libxml2
Fixed versions: 2.9.11-r0
libxml2
Fixed versions: 2.9.11-r0
libxml2
Fixed versions: 2.9.11-r0
Complete source record
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"modified": "2026-10-23T17:17:56.197262336Z",
"provider": "osv",
"upstream": [
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]
},
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"source_id": "core-osv",
"document_id": 415482,
"published_at": "2021-05-14T20:15:16.553+00:00"
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