CVE-2019-19956

xmlParseBalancedChunkMemoryRecover in parser.c in libxml2 before 2.9.10 has a memory leak related to newDoc->oldNs.

Published: 2019-12-24 Last update: 2025-12-03 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2019-19956 is rated High Risk (67.2/100): CVSS High severity, with high exploitation likelihood (EPSS 5.67%, 92th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +5.51% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2019-19956

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.15% 5.67% +5.51%
2 2025-11-21 4.92% 0.15% -4.76%
3 2025-11-18 — 4.92% —

Full EPSS history (17 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2019-19956

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2019-19956

OS Trackers for CVE-2019-19956

vendor priority summary link
alpine — CVE-2019-19956: 1 source package rows (libxml2); 26 state rows across 6 repos (3.10-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 1, open 25. https://security.alpinelinux.org/vuln/CVE-2019-19956
debian not yet assigned CVE-2019-19956 not yet assigned priority: Debian including 1 source packages (libxml2), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2019-19956
redhat medium — https://access.redhat.com/security/cve/CVE-2019-19956
suse medium CVE-2019-19956 severity moderate: SUSE including 444 source package names (0.1.0:libxml2-2-2.9.7-3.22.1, 0.1.75:libxml2-2-2.9.7-3.22.1, …), 623 product×package rows across 212 product lines (Container bci/bci-init, Container bci/dotnet-aspnet, … (212 product lines)): Fixed 441, Known Affected 157, Known Not Affected 25. https://www.suse.com/security/cve/CVE-2019-19956/
ubuntu low CVE-2019-19956 low priority: Ubuntu including 1 source packages (libxml2), 7 status rows across 7 suites (bionic, disco, eoan, focal, trusty, upstream, xenial): released 6, ignored 1. https://ubuntu.com/security/CVE-2019-19956

Affected software / configurations for CVE-2019-19956

Vendor Product Version Raw CPE
xmlsoft libxml2 < 2.9.10 cpe:2.3:a:xmlsoft:libxml2:*:*:*:*:*:*:*:*
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
oracle real_user_experience_insight 13.3.1.0 cpe:2.3:a:oracle:real_user_experience_insight:13.3.1.0:*:*:*:*:*:*:*
fedoraproject fedora 30 cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*
fedoraproject fedora 32 cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
canonical ubuntu_linux 12.04 cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:-:*:*:*
canonical ubuntu_linux 14.04 cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*
canonical ubuntu_linux 16.04 cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
canonical ubuntu_linux 18.04 cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
canonical ubuntu_linux 19.10 cpe:2.3:o:canonical:ubuntu_linux:19.10:*:*:*:*:*:*:*
netapp active_iq_unified_manager — cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:vmware_vsphere:*:*
netapp clustered_data_ontap — cpe:2.3:a:netapp:clustered_data_ontap:-:*:*:*:*:*:*:*
netapp clustered_data_ontap_antivirus_connector — cpe:2.3:a:netapp:clustered_data_ontap_antivirus_connector:-:*:*:*:*:*:*:*
netapp manageability_software_development_kit — cpe:2.3:a:netapp:manageability_software_development_kit:-:*:*:*:*:*:*:*
netapp ontap_select_deploy_administration_utility — cpe:2.3:a:netapp:ontap_select_deploy_administration_utility:-:*:*:*:*:*:*:*
netapp steelstore_cloud_integrated_storage — cpe:2.3:a:netapp:steelstore_cloud_integrated_storage:-:*:*:*:*:*:*:*
siemens sinema_remote_connect_server < 3.0 cpe:2.3:a:siemens:sinema_remote_connect_server:*:*:*:*:*:*:*:*

References for CVE-2019-19956

URL Tags
http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00047.html Broken Link
http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00005.html Broken Link
https://cert-portal.siemens.com/productcert/pdf/ssa-292794.pdf Third Party Advisory
https://gitlab.gnome.org/GNOME/libxml2/commit/5a02583c7e683896d84878bd90641d8d9b0d0549 Patch Third Party Advisory
https://lists.debian.org/debian-lts-announce/2019/12/msg00032.html Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/09/msg00009.html Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5R55ZR52RMBX24TQTWHCIWKJVRV6YAWI/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JDPF3AAVKUAKDYFMFKSIQSVVS3EEFPQH/
https://security.netapp.com/advisory/ntap-20200114-0002/ Third Party Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-103-08 Third Party Advisory US Government Resource
https://usn.ubuntu.com/4274-1/ Third Party Advisory
https://www.oracle.com/security-alerts/cpujul2020.html Third Party Advisory
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