Vulnerability-Lookup

RHSA-2026:72663

Vulnerability from csaf_opensuse - Published: 2026-09-28 00:00 - Updated: 2026-09-29 17:24

Summary

security update for expat

Severity

Important

Notes

Title of the patch: security update for expat

Description of the patch: This security update provides a functional equivalent of RHSA-2026:72663. The original Red Hat(R) advisory is available from the Red Hat web site at https://access.redhat.com/errata/RHSA-2026:72663.

Patchnames: RHSA-2026:72663

CVE-2026-66046

7.5 (High)


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

Affected products

Recommended 4 products

Product	Version	Remediation
Unresolved product id: SUSE Liberty Linux 9:expat-0:2.5.0-6.el9_8.5.i686	—	Vendor Fix
Unresolved product id: SUSE Liberty Linux 9:expat-0:2.5.0-6.el9_8.5.x86_64	—	Vendor Fix
Unresolved product id: SUSE Liberty Linux 9:expat-devel-0:2.5.0-6.el9_8.5.i686	—	Vendor Fix
Unresolved product id: SUSE Liberty Linux 9:expat-devel-0:2.5.0-6.el9_8.5.x86_64	—	Vendor Fix

Threats

Impact important

CVE-2026-93990

5.3 (Medium)


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

Affected products

Recommended 4 products, the same list as for CVE-2026-66046

Threats

Impact moderate

References

9 references

URL	Category
https://www.suse.com/support/security/rating/	external
https://ftp.suse.com/pub/projects/security/csaf/r…	self
https://www.suse.com/security/cve/CVE-2026-66046/	self
https://www.suse.com/security/cve/CVE-2026-93990/	self
https://www.suse.com/security/cve/CVE-2026-66046	external
https://bugzilla.suse.com/1275708	external
https://bugzilla.suse.com/1275915	external
https://www.suse.com/security/cve/CVE-2026-93990	external
https://bugzilla.suse.com/1282347	external

JSON

To clipboard

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}

CVE-2026-66046 (GCVE-0-2026-66046)

Vulnerability from cvelistv5 – Published: 2026-08-18 14:10 – Updated: 2026-08-21 11:20 X_Open Source

Title

Expat Denial of Service via storeAtts() Quadratic Complexity

Summary

Expat through 2.8.3 contains a denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function in xmlparse.c, where processing N specified attributes with non-normalized values triggers an O(N^2) linear scan of elementType->defaultAtts to determine CDATA status. A remote unauthenticated attacker can supply a single well-formed XML document of a few megabytes to an application parsing untrusted XML to cause excessive CPU consumption, resulting in denial of service without requiring authentication, external entity resolution, or non-default parser options.

Severity

8.7 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

7.5 (High)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-20 13:48 UTC

CWE

CWE-407 - Inefficient Algorithmic Complexity

Assigner

VulnCheck mitre root

References

2 references

URL	Tags
https://github.com/libexpat/libexpat/pull/1321	issue-tracking
https://www.vulncheck.com/advisories/expat-denial…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
libexpat project	libexpat	Affected: 0 , ≤ 2.8.3 (semver)

Date Public

2026-08-13 00:00

Credits

Fabian Wahle (Hap Security) Sebastian Pipping VulnCheck

Show details on NVD website

JSON

To clipboard

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CVE-2026-93990 (GCVE-0-2026-93990)

Vulnerability from cvelistv5 – Published: 2026-09-19 22:58 – Updated: 2026-09-28 16:11

Title

Expat before 2.8.5 Malformed UTF-16 Acceptance via Unchecked Surrogate

Summary

Expat before 2.8.5 fails to validate that a high surrogate in UTF-16 input is followed by a low surrogate, allowing malformed UTF-16 sequences to be accepted. Attackers can supply UTF-16 encoded XML containing lone high surrogates that consume the following code unit, causing Expat to pass unpaired surrogates to applications built with XML_UNICODE and to silently replace input characters in other builds.

Severity

8.7 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

7.5 (High)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-21 15:10 UTC

CWE

CWE-176 - Improper Handling of Unicode Encoding

Assigner

VulnCheck mitre root

References

6 references

URL	Tags
https://github.com/libexpat/libexpat/pull/1282	issue-trackingpatch
https://github.com/libexpat/libexpat/commit/ff6e1…	patch
https://github.com/libexpat/libexpat/releases/tag…	release-notes
https://blog.hartwork.org/posts/expat-2-8-5-released/	vendor-advisory
https://github.com/libexpat/libexpat	product
https://www.vulncheck.com/advisories/expat-throug…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
libexpat	libexpat	Affected: 0 , < 2.8.5 (semver) Unaffected: 2.8.5 (semver) cpe:2.3:a:libexpat_project:libexpat::::::::

Date Public

2026-09-18 00:00

Credits

Kartik Kenchi (netliomax25-code)

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

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Confirmed: The vulnerability has been validated from an analyst's perspective.
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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.

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

RHSA-2026:72663

CVE-2026-66046 (GCVE-0-2026-66046)

CVE-2026-93990 (GCVE-0-2026-93990)

Tags

Sightings

Nomenclature

Related by attack behaviour