Vulnerability-Lookup

rlsa-2026:64812

Vulnerability from osv_rocky

Published

2026-09-09 12:05

Modified

2026-09-15 12:12

Summary

Moderate: expat security update

Details

Expat is a C library for parsing XML documents.

Security Fix(es):

expat: libexpat: Use-after-free vulnerability due to improper handler call depth tracking (CVE-2026-50219)
expat: libexpat: Arbitrary Code Execution via Heap-based Buffer Overflow (CVE-2026-56132)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Severity

6.9 (Medium)


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

Credits

Rocky Enterprise Software Foundation

Red Hat

References

URL

Type

	https://errata.rockylinux.org/RLSA-2026:64812	ADVISORY
	https://bugzilla.redhat.com/show_bug.cgi?id=2484620	REPORT
	https://bugzilla.redhat.com/show_bug.cgi?id=2490669	REPORT
	https://access.redhat.com/errata/RHSA-2026:64812	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Rocky Linux:9",
        "name": "expat",
        "purl": "pkg:rpm/rocky-linux/expat?distro=rocky-linux-9\u0026epoch=0"
      },
      "ranges": [
        {
          "database_specific": {
            "yum_repository": "BaseOS"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0:2.5.0-6.el9_8.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "credits": [
    {
      "name": "Rocky Enterprise Software Foundation"
    },
    {
      "name": "Red Hat"
    }
  ],
  "database_specific": {
    "license": "CC-BY-4.0",
    "license_url": "https://creativecommons.org/licenses/by/4.0/",
    "source_advisory": "RHSA-2026:64812"
  },
  "details": "Expat is a C library for parsing XML documents.\n\nSecurity Fix(es):\n\n* expat: libexpat: Use-after-free vulnerability due to improper handler call depth tracking (CVE-2026-50219)\n\n* expat: libexpat: Arbitrary Code Execution via Heap-based Buffer Overflow (CVE-2026-56132)\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.",
  "id": "RLSA-2026:64812",
  "modified": "2026-09-15T12:12:56.895045Z",
  "published": "2026-09-09T12:05:17.368443Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://errata.rockylinux.org/RLSA-2026:64812"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2484620"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2490669"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:64812"
    }
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Moderate: expat security update",
  "upstream": [
    "CVE-2026-50219",
    "CVE-2026-56132"
  ]
}

CVE-2026-50219 (GCVE-0-2026-50219)

Vulnerability from cvelistv5 – Published: 2026-06-04 04:20 – Updated: 2026-06-04 12:36

Summary

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. Thus, a use-after-free can occur,

Severity

4.9 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-04 12:36 UTC

CWE

CWE-416 - Use After Free

Assigner

mitre mitre root

References

1 reference

URL	Tags
https://github.com/libexpat/libexpat/pull/1246

Impacted products

1 product

Vendor	Product	Version
libexpat project	libexpat	Affected: 0 , < 2.8.2 (semver) cpe:2.3:a:libexpat_project:libexpat::::::::

Show details on NVD website

JSON

To clipboard

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CVE-2026-56132 (GCVE-0-2026-56132)

Vulnerability from cvelistv5 – Published: 2026-06-19 03:00 – Updated: 2026-06-22 14:59

Summary

In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers.

Severity

6.9 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-22 14:59 UTC

CWE

CWE-821 - Incorrect Synchronization

Assigner

mitre mitre root

References

1 reference

URL	Tags
https://github.com/libexpat/libexpat/pull/1272

Impacted products

1 product

Vendor	Product	Version
libexpat project	libexpat	Affected: 0 , < 2.8.2 (semver) cpe:2.3:a:libexpat_project:libexpat::::::::

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

rlsa-2026:64812

Vulnerability from osv_rocky

CVE-2026-50219 (GCVE-0-2026-50219)

CVE-2026-56132 (GCVE-0-2026-56132)

Tags

Sightings

Nomenclature