CVE-2026-56403
published 2026-06-21CVE-2026-56403: libexpat before 2.8.2 has an integer overflow in storeAtts.
PriorityP432medium6.9CVSS 3.1
AVLACHPRNUINSUCHIHAL
EPSS
0.17%
6.1th percentile
libexpat before 2.8.2 has an integer overflow in storeAtts.
Affected
9 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| ansible-automation-platform-26 | lightspeed-chatbot-rhel9 | — | — |
| ansible-automation-platform-27 | lightspeed-chatbot-rhel9 | — | — |
| debian | expat | — | — |
| exploit-intelligence-tech-preview | vulnerability-analysis-rhel9 | — | — |
| libexpat_project | libexpat | < 2.8.2 | 2.8.2 |
| rhoai | odh-llama-stack-core-rhel9 | — | — |
| rhoai | odh-mlflow-rhel9 | — | — |
| rhoai | odh-trustyai-garak-lls-provider-dsp-rhel9 | — | — |
| ubuntu | expat | — | — |
CVSS provenance
nvdv3.16.9MEDIUMCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L
vendor_ubuntu7.5HIGH
vendor_redhat6.9MEDIUM
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VulDB
libexpat up to 2.8.1 integer overflow (EUVD-2026-38180)
vuldb·2026-06-21·CVSS 6.9
CVE-2026-56403 [MEDIUM] libexpat up to 2.8.1 integer overflow (EUVD-2026-38180)
A vulnerability classified as problematic has been found in libexpat up to 2.8.1. Affected by this issue is some unknown functionality. This manipulation causes integer overflow.
This vulnerability is tracked as CVE-2026-56403. The attack is restricted to local execution. No exploit exists.
It is recommended to upgrade the affected component.
GHSA
libexpat before 2.8.2 has an integer overflow in storeAtts.
ghsa_unreviewed·2026-06-21
CVE-2026-56403 [MEDIUM] CWE-190 libexpat before 2.8.2 has an integer overflow in storeAtts.
libexpat before 2.8.2 has an integer overflow in storeAtts.
Ubuntu
Expat vulnerabilities
vendor_ubuntu·2026-09-21·CVSS 7.5
CVE-2026-50219 [HIGH] Expat vulnerabilities
Title: Expat vulnerabilities
Summary: Several security issues were fixed in Expat.
It was discovered that Expat could be made to allocate large amounts of
memory when parsing a small crafted document. An attacker could possibly
use this issue to cause Expat to consume resources, leading to a denial of
service. This issue was only addressed in Ubuntu 24.04 LTS.
(CVE-2025-59375)
It was discovered that Expat incorrectly handled empty external parameter
entity content. An attacker could possibly use this issue to cause Expat to
crash, resulting in a denial of service. (CVE-2026-32776)
It was discovered that Expat incorrectly handled certain DTD content. An
attacker could possibly use this issue to cause Expat to enter an infinite
loop, resulting in a denial of service. (CVE-2026-32777)
It
Red Hat
libexpat: libexpat: Arbitrary code execution due to integer overflow in storeAtts
vendor_redhat·2026-06-21·CVSS 6.9
CVE-2026-56403 [MEDIUM] CWE-190 libexpat: libexpat: Arbitrary code execution due to integer overflow in storeAtts
libexpat: libexpat: Arbitrary code execution due to integer overflow in storeAtts
libexpat before 2.8.2 has an integer overflow in storeAtts.
A flaw was found in libexpat. An integer overflow vulnerability exists in the `storeAtts` function. This flaw could allow an attacker to corrupt memory, leading to a denial of service, information disclosure, or potentially arbitrary code execution, compromising the integrity and confidentiality of data.
Package: exploit-intelligence-tech-preview/vulnerability-analysis-rhel9 (Exploit Intelligence) - Under investigation
Package: ansible-automation-platform-26/lightspeed-chatbot-rhel9 (Red Hat Ansible Automation Platform 2) - Fix deferred
Package: ansible-automation-platform-27/lightspeed-chatbot-rhel9 (Red Hat Ansible Automation Platform 2) - Fix
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-56403 mingw-expat: libexpat: Arbitrary code execution due to integer overflow in storeAtts [fedora-43]
bugzilla·2026-10-15·CVSS 6.9
CVE-2026-56403 [MEDIUM] CVE-2026-56403 mingw-expat: libexpat: Arbitrary code execution due to integer overflow in storeAtts [fedora-43]
CVE-2026-56403 mingw-expat: libexpat: Arbitrary code execution due to integer overflow in storeAtts [fedora-43]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
libexpat before 2.8.2 has an integer overflow in storeAtts.
Bugzilla
CVE-2026-56403 expat: libexpat: Arbitrary code execution due to integer overflow in storeAtts [fedora-44]
bugzilla·2026-10-15·CVSS 6.9
CVE-2026-56403 [MEDIUM] CVE-2026-56403 expat: libexpat: Arbitrary code execution due to integer overflow in storeAtts [fedora-44]
CVE-2026-56403 expat: libexpat: Arbitrary code execution due to integer overflow in storeAtts [fedora-44]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
libexpat before 2.8.2 has an integer overflow in storeAtts.
Bugzilla
CVE-2026-56403 mingw-expat: libexpat: Arbitrary code execution due to integer overflow in storeAtts [fedora-44]
bugzilla·2026-10-15·CVSS 6.9
CVE-2026-56403 [MEDIUM] CVE-2026-56403 mingw-expat: libexpat: Arbitrary code execution due to integer overflow in storeAtts [fedora-44]
CVE-2026-56403 mingw-expat: libexpat: Arbitrary code execution due to integer overflow in storeAtts [fedora-44]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
libexpat before 2.8.2 has an integer overflow in storeAtts.
Bugzilla
CVE-2026-56403 expat: libexpat: Arbitrary code execution due to integer overflow in storeAtts [fedora-43]
bugzilla·2026-10-15·CVSS 6.9
CVE-2026-56403 [MEDIUM] CVE-2026-56403 expat: libexpat: Arbitrary code execution due to integer overflow in storeAtts [fedora-43]
CVE-2026-56403 expat: libexpat: Arbitrary code execution due to integer overflow in storeAtts [fedora-43]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
libexpat before 2.8.2 has an integer overflow in storeAtts.
Bugzilla
CVE-2026-56403 libexpat: libexpat: Arbitrary code execution due to integer overflow in storeAtts
bugzilla·2026-06-21·CVSS 6.9
CVE-2026-56403 [MEDIUM] CVE-2026-56403 libexpat: libexpat: Arbitrary code execution due to integer overflow in storeAtts
CVE-2026-56403 libexpat: libexpat: Arbitrary code execution due to integer overflow in storeAtts
libexpat before 2.8.2 has an integer overflow in storeAtts.
2026-06-21
Published