CVE catalog

CVE-2021-3518

libxml2: CVE-2021-3518

Severity: High · CVSS 8.8CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Published: Apr 22, 2021, 12:00:00 AM UTC
Source: [NVD] · [CVE record]
EPSS: 21.86% · Oct 25, 2026

There's a flaw in libxml2 in versions before 2.9.11. An attacker who is able to submit a crafted file to be processed by an application linked with libxml2 could trigger a use-after-free. The greatest impact from this flaw is to confidentiality, integrity, and availability.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	libxml2	sid	`2.15.4+dfsg-1`	fixed
Debian	libxml2	forky	`2.15.4+dfsg-1`	fixed
Debian	libxml2	trixie	`2.12.7+dfsg+really2.9.14-2.1+deb13u3`	fixed
Debian	libxml2	trixie-security	`2.12.7+dfsg+really2.9.14-2.1+deb13u1`	fixed
Debian	libxml2	bookworm	`2.9.14+dfsg-1.3~deb12u6`	fixed
Debian	libxml2	bookworm-security	`2.9.14+dfsg-1.3~deb12u4`	fixed
Cpe	libxml2	Not reported	`2.9.11`	fixed
Cpe	debian_linux	Not reported	Not reported	unknown
Cpe	jboss_core_services	Not reported	Not reported	unknown
Cpe	enterprise_linux	Not reported	Not reported	unknown
Cpe	fedora	Not reported	Not reported	unknown
Cpe	active_iq_unified_manager	Not reported	Not reported	unknown
Cpe	clustered_data_ontap	Not reported	Not reported	unknown
Cpe	clustered_data_ontap_antivirus_connector	Not reported	Not reported	unknown
Cpe	manageability_software_development_kit	Not reported	Not reported	unknown
Cpe	ontap_select_deploy_administration_utility	Not reported	Not reported	unknown
Cpe	snapdrive	Not reported	Not reported	unknown
Cpe	hci_h410c_firmware	Not reported	Not reported	unknown
Cpe	communications_cloud_native_core_network_function_cloud_native_environment	Not reported	Not reported	unknown
Cpe	enterprise_manager_base_platform	Not reported	Not reported	unknown
Cpe	enterprise_manager_ops_center	Not reported	Not reported	unknown
Cpe	mysql_workbench	Not reported	Not reported	unknown
Cpe	peoplesoft_enterprise_peopletools	Not reported	Not reported	unknown
Cpe	real_user_experience_insight	Not reported	Not reported	unknown
Alpine	libxml2	3.10	`2.9.9-r5`	fixed
Alpine	libxml2	3.11	`2.9.10-r5`	fixed
Alpine	libxml2	3.12	`2.9.10-r6`	fixed
Alpine	libxml2	3.13	`2.9.10-r7`	fixed
Alpine	libxml2	3.14	`2.9.11-r0`	fixed
Alpine	libxml2	3.15	`2.9.11-r0`	fixed
Alpine	libxml2	3.16	`2.9.11-r0`	fixed
Alpine	libxml2	3.17	`2.9.11-r0`	fixed
Alpine	libxml2	3.18	`2.9.11-r0`	fixed
Alpine	libxml2	3.19	`2.9.11-r0`	fixed
Alpine	libxml2	3.20	`2.9.11-r0`	fixed
Alpine	libxml2	3.21	`2.9.11-r0`	fixed
Alpine	libxml2	3.22	`2.9.11-r0`	fixed
Alpine	libxml2	3.23	`2.9.11-r0`	fixed
Alpine	libxml2	3.24	`2.9.11-r0`	fixed
Ubuntu	libxml2	pro	`2.9.2+zdfsg1-4`	vulnerable
Ubuntu	libxml2	pro	`2.9.2+zdfsg1-4ubuntu1`	vulnerable
Ubuntu	libxml2	pro	`2.9.2+zdfsg1-4ubuntu2`	vulnerable
Ubuntu	libxml2	pro	`2.9.2+zdfsg1-4ubuntu3`	vulnerable
Ubuntu	libxml2	pro	`2.9.3+dfsg1-1`	vulnerable
Ubuntu	libxml2	pro	`2.9.3+dfsg1-1ubuntu0.1`	vulnerable
Ubuntu	libxml2	pro	`2.9.3+dfsg1-1ubuntu0.2`	vulnerable
Ubuntu	libxml2	pro	`2.9.3+dfsg1-1ubuntu0.3`	vulnerable
Ubuntu	libxml2	pro	`2.9.3+dfsg1-1ubuntu0.4`	vulnerable
Ubuntu	libxml2	pro	`2.9.3+dfsg1-1ubuntu0.5`	vulnerable
Ubuntu	libxml2	pro	`2.9.3+dfsg1-1ubuntu0.6`	vulnerable
Ubuntu	libxml2	pro	`2.9.3+dfsg1-1ubuntu0.7`	vulnerable
Ubuntu	libxml2	pro	`2.9.3+dfsg1-1ubuntu0.7+esm1`	fixed
Ubuntu	libxml2	18.04	`2.9.4+dfsg1-4ubuntu1`	vulnerable
Ubuntu	libxml2	18.04	`2.9.4+dfsg1-5ubuntu1`	vulnerable
Ubuntu	libxml2	18.04	`2.9.4+dfsg1-5ubuntu2`	vulnerable
Ubuntu	libxml2	18.04	`2.9.4+dfsg1-5.1ubuntu1`	vulnerable
Ubuntu	libxml2	18.04	`2.9.4+dfsg1-5.2ubuntu1`	vulnerable
Ubuntu	libxml2	18.04	`2.9.4+dfsg1-6.1ubuntu1`	vulnerable
Ubuntu	libxml2	18.04	`2.9.4+dfsg1-6.1ubuntu1.2`	vulnerable
Ubuntu	libxml2	18.04	`2.9.4+dfsg1-6.1ubuntu1.3`	vulnerable
Ubuntu	libxml2	18.04	`2.9.4+dfsg1-6.1ubuntu1.4`	fixed
Ubuntu	libxml2	20.04	`2.9.4+dfsg1-7ubuntu3`	vulnerable
Ubuntu	libxml2	20.04	`2.9.4+dfsg1-7ubuntu5`	vulnerable
Ubuntu	libxml2	20.04	`2.9.4+dfsg1-8ubuntu1`	vulnerable
Ubuntu	libxml2	20.04	`2.9.4+dfsg1-8ubuntu2`	vulnerable
Ubuntu	libxml2	20.04	`2.9.4+dfsg1-8ubuntu3`	vulnerable
Ubuntu	libxml2	20.04	`2.9.10+dfsg-1ubuntu3`	vulnerable
Ubuntu	libxml2	20.04	`2.9.10+dfsg-4build1`	vulnerable
Ubuntu	libxml2	20.04	`2.9.10+dfsg-5`	vulnerable
Ubuntu	libxml2	20.04	`2.9.10+dfsg-5ubuntu0.20.04.1`	fixed

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	libxml2	source	sid	`2.9.10+dfsg-6.6`	not yet assigned	Not reported	[987737]
Debian	libxml2	source	forky	`2.9.10+dfsg-6.6`	not yet assigned	Not reported	[987737]
Debian	libxml2	source	trixie	`2.9.10+dfsg-6.6`	not yet assigned	Not reported	[987737]
Debian	libxml2	source	bookworm	`2.9.10+dfsg-6.6`	not yet assigned	Not reported	[987737]
Cpe	libxml2	cpe	Not reported	`2.9.11`	Not reported	NVD-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.10	`2.9.9-r5`	Not reported	ALPINE-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.11	`2.9.10-r5`	Not reported	ALPINE-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.12	`2.9.10-r6`	Not reported	ALPINE-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.13	`2.9.10-r7`	Not reported	ALPINE-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.14	`2.9.11-r0`	Not reported	ALPINE-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.15	`2.9.11-r0`	Not reported	ALPINE-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.16	`2.9.11-r0`	Not reported	ALPINE-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.17	`2.9.11-r0`	Not reported	ALPINE-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.18	`2.9.11-r0`	Not reported	ALPINE-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.19	`2.9.11-r0`	Not reported	ALPINE-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.20	`2.9.11-r0`	Not reported	ALPINE-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.21	`2.9.11-r0`	Not reported	ALPINE-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.22	`2.9.11-r0`	Not reported	ALPINE-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.23	`2.9.11-r0`	Not reported	ALPINE-CVE-2021-3518	Not reported
Alpine	libxml2	apk	3.24	`2.9.11-r0`	Not reported	ALPINE-CVE-2021-3518	Not reported
Ubuntu	libxml2	deb	pro	`2.9.3+dfsg1-1ubuntu0.7+esm1`	Not reported	UBUNTU-CVE-2021-3518	Not reported
Ubuntu	libxml2	deb	18.04	`2.9.4+dfsg1-6.1ubuntu1.4`	Not reported	UBUNTU-CVE-2021-3518	Not reported
Ubuntu	libxml2	deb	20.04	`2.9.10+dfsg-5ubuntu0.20.04.1`	Not reported	UBUNTU-CVE-2021-3518	Not reported

[Debian bug #987737]

OpenFactory catalog packages

Matching against OpenFactory catalog package versions is in progress.

[Debian 12 (Bookworm)]

[libxml2]Unknown
Details (4)
- 2.9.14+dfsg-1.3~deb12u6 · amd64 · bookworm
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u6 · arm64 · bookworm
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u4 · amd64 · bookworm-security
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u4 · arm64 · bookworm-security
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
[libxml2-dev]Unknown
Source package: [libxml2]
Details (4)
- 2.9.14+dfsg-1.3~deb12u6 · amd64 · bookworm
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u6 · arm64 · bookworm
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u4 · amd64 · bookworm-security
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u4 · arm64 · bookworm-security
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
[libxml2-doc]Unknown
Source package: [libxml2]
Details (4)
- 2.9.14+dfsg-1.3~deb12u6 · all · bookworm
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u6 · all · bookworm
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u4 · all · bookworm-security
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u4 · all · bookworm-security
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
[libxml2-utils]Unknown
Source package: [libxml2]
Details (4)
- 2.9.14+dfsg-1.3~deb12u6 · amd64 · bookworm
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u6 · arm64 · bookworm
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u4 · amd64 · bookworm-security
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u4 · arm64 · bookworm-security
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
[python3-libxml2]Unknown
Source package: [libxml2]
Details (4)
- 2.9.14+dfsg-1.3~deb12u6 · amd64 · bookworm
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u6 · arm64 · bookworm
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u4 · amd64 · bookworm-security
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm
- 2.9.14+dfsg-1.3~deb12u4 · arm64 · bookworm-security
  Fixed · Fixed: 2.9.10+dfsg-6.6
  dsa · libxml2 · debian · bookworm

Observed: Oct 23, 2026, 5:58:27 PM UTC

References

[CERT-Bund public advisories] · [CISA cybersecurity advisories] · [Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]