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No exploitation reportedFix available

CVE-2026-113351

libexpat 2.7.2 through 2.9.0 Denial of Service via XML_ParserReset

No exploitation reported by the sources we read.

  • Published2026-10-20
  • WeaknessCWE-909

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

libexpat 2.7.2 through 2.9.0 contains a denial of service vulnerability because XML_ParserReset zeroes the direct byte count but never offsets tracked heap allocations. Attackers can submit a large XML document so later documents on the same reset parser fail with XML_ERROR_NO_MEMORY until it is recreated.

Timeline

dates in UTC
  1. 2026-10-2011:17CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-11-03 21:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-113351?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-113351?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
Libexpat project libexpat
BranchAffectedFixed in
2.x≥ 2.7.2, ≤ 2.9.0no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Products declared by the CNA1 product

As VulnCheck, the CNA that assigned this CVE, declared them in the CVE record; versions as written.

Source: the CNA record (CVE Program), © The MITRE Corporation,CVE Terms of UseCVE recordupdated 2026-10-20

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • coin3Ubuntu:Pro:18.04:LTSall versions · no fixed version listedand 4 other packages
  • expatWolfiall versions · fixed in 2.10.0-r0and 3 other packages
  • expatUbuntu:Pro:20.04:LTSall versions · no fixed version listedand 3 other packages
  • expatRoot:Debian:13all versions · fixed in 2.9.0-1~deb13u1.aikido.25and 1 other package
  • expatRoot:Debian:13all versions · fixed in 2.9.0-1~deb13u1.aikido.24and 1 other package
  • expatRoot:Debian:12all versions · fixed in 2.5.0-1+deb12u5.aikido.28and 1 other package
  • expatEchoall versions · fixed in 2.9.0-1+e3
  • expatDebian:14all versions · no fixed version listed

26 more package ranges on OSV.dev

Vendor advisories

  • CVE-2026-113351 Red Hat Product Security10 products fixed · 45 known affected

    expat: expat: Denial of Service via improper memory tracking in XML_ParserReset

    expat as a component of Red Hat Enterprise Linux 10 · expat-devel as a component of Red Hat Enterprise Linux 10 · expat.src as a component of Red Hat Enterprise Linux 10 · +42 more

  • RHSA-2026:90325 Red Hat Product Security10 products fixed

    Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update

Full record on NVD

Fix

  1. Vendor fix Red Hat Product Security RHSA-2026:90325 · 10 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
  2. No fix available, says the vendor Red Hat Product Security CVE-2026-113351 · 34 productsFix deferred
  3. No fix available, says the vendor Red Hat Product Security CVE-2026-113351 · 6 productsAffected
  4. No fix planned, says the vendor Red Hat Product Security CVE-2026-113351 · 5 productsOut of support scope

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS 4.0 vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Published
2026-10-20
Last Modified
2026-11-03
NVD status
Analyzed
GitHub Advisory
GHSA-6r6q-9jmv-gg3h

Frequently asked questions

What is CVE-2026-113351?

libexpat 2.7.2 through 2.9.0 contains a denial of service vulnerability because XML_ParserReset zeroes the direct byte count but never offsets tracked heap allocations. Attackers can submit a large XML document so later documents on the same reset parser fail with XML_ERROR_NO_MEMORY until it is recreated.

Is CVE-2026-113351 actively exploited?

Active exploitation of CVE-2026-113351 has not been confirmed. Its EPSS score was 0.5% on 2026-11-03, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-113351?

CVE-2026-113351 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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