CVE-2026-45186
In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input.
02 Description
In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input.
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.
- EPSS probability
- 0.47% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 41.0% of scored records. A rank, not a probability.
- NVD base score
- 7.5 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- NVD analysis status
- Modified. NVD last modified this record on 2026-09-16.
- Red Hat severity
- Important. 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
- 2026-05-10 06:36Z5 MO AGO
- Last updated
- 2026-10-15 01:19Z14 DAYS AGO
- Reserved
- 2026-05-10
- Assigning CNA
- mitre
- Record state
- PUBLISHED
- Severity
- Low (CVSS 2.9)
- CNA CVSS vector
- CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
- Weaknesses
- CWE-407Inefficient Algorithmic ComplexityClass
- Data version
- 5.2
- Document digest
- f0c51b6e76fa5795687b78ebe8a201020ce59b4cbfe7d9d21b99a9d003bf011b
05 Affected products
06 References
- github.comhttps://github.com/libexpat/libexpat/pull/1216
- www.openwall.comhttp://www.openwall.com/lists/oss-security/2026/05/11/16
- access.redhat.comhttps://access.redhat.com/security/cve/CVE-2026-45186
- bugzilla.redhat.comRHBZ#2468575https://bugzilla.redhat.com/show_bug.cgi?id=2468575
- security.access.redhat.comhttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-45186.json
- access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:22715
- access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:23230
- access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:22721
- access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:29197
- access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:27201
- access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:58981
- access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:26319
- cert-portal.siemens.comhttps://cert-portal.siemens.com/productcert/html/ssa-082556.html
07 Fixed in
AlmaLinux 8
- expat Fixed in 2.5.0-2.el8_10
- expat-devel Fixed in 2.5.0-2.el8_10
Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
AlmaLinux 9
- expat Fixed in 2.5.0-6.el9_8.1
- expat-devel Fixed in 2.5.0-6.el9_8.1
Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
AlmaLinux 10
- expat Fixed in 2.7.3-1.el10_2.1
- expat-devel Fixed in 2.7.3-1.el10_2.1
- thunderbird Fixed in 153.5.0-1.el10_2.alma.1
Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
CloudLinux 8
- expat Fixed in 2.5.0-2.el8_10
- expat-devel Fixed in 2.5.0-2.el8_10
Derived from AlmaLinux 8. Partial coverage: only packages taken from AlmaLinux 8 are listed.
Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
CloudLinux 9
- expat Fixed in 2.5.0-6.el9_8.1
- expat-devel Fixed in 2.5.0-6.el9_8.1
Derived from AlmaLinux 9. Partial coverage: only packages taken from AlmaLinux 9 are listed.
Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
CloudLinux 10
- expat Fixed in 2.7.3-1.el10_2.1
- expat-devel Fixed in 2.7.3-1.el10_2.1
- thunderbird Fixed in 153.5.0-1.el10_2.alma.1
Derived from AlmaLinux 10. Partial coverage: only packages taken from AlmaLinux 10 are listed.
Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
Debian 12
- expat Fixed in 2.5.0-1+deb12u4
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 2.8.0-2
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 16.04 LTS
- cadaver No fix yet
- gdcm No fix yet
- insighttoolkit4 No fix yet
- matanza No fix yet
- smart No fix yet
- tdom No fix yet
- wbxml2 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 18.04 LTS
- cadaver No fix yet
- gdcm No fix yet
- insighttoolkit4 No fix yet
- matanza No fix yet
- smart No fix yet
- tdom No fix yet
- vnc4 No fix yet
- wbxml2 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 20.04 LTS
- cadaver No fix yet
- insighttoolkit4 No fix yet
- matanza No fix yet
- tdom No fix yet
- wbxml2 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 22.04 LTS
- cadaver No fix yet
- expat No fix yet
- insighttoolkit4 No fix yet
- libxmltok No fix yet
- matanza No fix yet
- tdom No fix yet
- wbxml2 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 24.04 LTS
- cadaver No fix yet
- expat Fixed in 2.6.1-2ubuntu0.5
- libxmltok No fix yet
- matanza No fix yet
- tdom No fix yet
- wbxml2 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 25.10
- cadaver No fix yet
- expat No fix yet
- matanza No fix yet
- swish-e No fix yet
- tdom No fix yet
- wbxml2 No fix yet
- xmlrpc-c No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 26.04 LTS
- cadaver No fix yet
- expat Fixed in 2.7.4-1ubuntu0.1
- matanza No fix yet
- tdom No fix yet
- wbxml2 No fix yet
- xmlrpc-c No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 26.10
- cadaver No fix yet
- matanza No fix yet
- swish-e No fix yet
- tdom No fix yet
- wbxml2 No fix yet
- xmlrpc-c No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 14.04 LTS
- coin3 No fix yet
- expat No fix yet
- vnc4 No fix yet
- vtk No fix yet
- xmlrpc-c No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 16.04 LTS
- ayttm No fix yet
- cableswig No fix yet
- coin3 No fix yet
- expat No fix yet
- libxmltok No fix yet
- swish-e No fix yet
- vnc4 No fix yet
- vtk No fix yet
- xmlrpc-c No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 18.04 LTS
- coin3 No fix yet
- expat No fix yet
- libxmltok No fix yet
- swish-e No fix yet
- xmlrpc-c No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 20.04 LTS
- expat No fix yet
- libxmltok No fix yet
- swish-e No fix yet
- xmlrpc-c No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 22.04 LTS
- swish-e No fix yet
- xmlrpc-c No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 24.04 LTS
- swish-e No fix yet
- xmlrpc-c No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 26.04 LTS
- swish-e No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.