01 Record

CVE-2026-50219

libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_GetBuffer, XML_Parse, XML_ParseBuffer, XML_ParserFree, or XML_ParserReset from within handlers in cases of a policy violation.

MediumPUBLISHEDCNA: mitre

CNA base score4.9 CVSS v3.xCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L

View raw JSON

02 Description

libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_GetBuffer, XML_Parse, XML_ParseBuffer, XML_ParserFree, or XML_ParserReset from within handlers in cases of a policy violation.

03 Exploitation and scoring

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.18% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 7.6% of scored records. A rank, not a probability.

NVD base score

5.9 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

NVD analysis status

Analyzed. NVD last modified this record on 2026-07-22.

Red Hat severity

Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

04 Metadata

Published

2026-06-04 04:20Z4 MO AGO

Last updated

2026-06-04 12:36Z4 MO AGO

Reserved

2026-06-04

Assigning CNA

mitre

Record state

PUBLISHED

Severity

Medium (CVSS 4.9)

CNA CVSS vector

CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L

Weaknesses

CWE-416Use After FreeVariant
CWE-911Improper Update of Reference CountBase

Data version

5.2

Document digest

b4cb22fcdba4c4ff84644f074989e2e75fdc936e0803e0034a62b4e6b4c18994

05 Affected products

VendorProductVersionsPlatforms

libexpat projectlibexpat0 to < 2.8.2—

06 References

github.comhttps://github.com/libexpat/libexpat/pull/1246

07 Fixed in

AlmaLinux 8

expat
Fixed in 2.5.0-2.el8_10.2
expat-devel
Fixed in 2.5.0-2.el8_10.2

AlmaLinux 9

expat
Fixed in 2.5.0-6.el9_8.3
expat-devel
Fixed in 2.5.0-6.el9_8.3

AlmaLinux 10

expat
Fixed in 2.7.3-1.el10_2.3
expat-devel
Fixed in 2.7.3-1.el10_2.3

CloudLinux 8

expat
Fixed in 2.5.0-2.el8_10.2
expat-devel
Fixed in 2.5.0-2.el8_10.2

Derived from AlmaLinux 8. Partial coverage: only packages taken from AlmaLinux 8 are listed.

CloudLinux 9

expat
Fixed in 2.5.0-6.el9_8.3
expat-devel
Fixed in 2.5.0-6.el9_8.3

Derived from AlmaLinux 9. Partial coverage: only packages taken from AlmaLinux 9 are listed.

CloudLinux 10

expat
Fixed in 2.7.3-1.el10_2.3
expat-devel
Fixed in 2.7.3-1.el10_2.3

Derived from AlmaLinux 10. Partial coverage: only packages taken from AlmaLinux 10 are listed.

Debian 12

expat
Fixed in 2.5.0-1+deb12u3

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Debian 13

expat
Fixed in 2.8.2-1~deb13u1

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Debian 14

expat
Fixed in 2.8.2-1

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.