Vulnerability · CVE-2026-76956
In libexpat 2.8.2 and 2.8.3 before 2.8.4, misinterpretation of getentropy's return code leads to insufficient entropy, which results in being vulnerable to hash flooding attacks, c
Published Aug 20, 2026 · catalog updated Oct 16, 2026 · In libexpat 2.8.2 and
Check if you run it
No confirmed exploitation is on record for CVE-2026-76956. EPSS is 0.29%. Act only if a listed version of In libexpat 2.8.2 and is installed.
Gaps on this record
- The stored product name is a package slug. The name on this page is taken from the title (In libexpat 2.8.2 and).
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- High7.5
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.29%
- Remediation
- Advisory link
- Affected products
- Debian:13 expat · Debian:14 expat
In libexpat 2.8.2 and 2.8.3 before 2.8.4, misinterpretation of getentropy's return code leads to insufficient entropy, which results in being vulnerable to hash flooding attacks, causing a denial of service via crafted XML content.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- Debian:13 expat0 → 2.9.0-1~deb13u1
- Debian:14 expat0 → 2.8.4-1
How to fix CVE-2026-76956
Recommended remediation
A patch or advisory reference is linked. Open the original publisher for availability by product version.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-76956. EPSS is 0.29%. Act only if a listed version of In libexpat 2.8.2 and is installed.
Which versions are affected?
Compare what you have installed with 0 → 2.9.0-1~deb13u1, 0 → 2.8.4-1. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 0.29%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Technology hubs
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Aug 20, 2026 · OpenSSF OSV / OSV Scanner
Detected
In libexpat 2.8.2 and 2.8.3 before 2.8.4, misinterpretation of getentropy's return code leads to insufficient entropy, which results in being vulnerable to hash flooding attacks, causing a denial of service via crafted XML content.
Oct 16, 2026 · OpenSSF OSV / OSV Scanner
Fix available
expat fixed in 2.9.0-1~deb13u1; expat fixed in 2.8.4-1
Oct 16, 2026 · OpenSSF OSV / OSV Scanner
Fix available
expat fixed in 2.9.0-1~deb13u1
Oct 16, 2026 · OpenSSF OSV / OSV Scanner
Fix available
expat fixed in 2.8.4-1
Oct 16, 2026 · OpenSSF OSV / OSV Scanner
Updated
In libexpat 2.8.2 and 2.8.3 before 2.8.4, misinterpretation of getentropy's return code leads to insufficient entropy, which results in being vulnerable to hash flooding attacks, causing a denial of service via crafted XML content.
Sources
- CVE.orgVulnerability recordCVE-2026-76956
Official CVE identifier
cve.org - Debian Security AdvisoriesVendor advisoryCVE-2026-76956
[SECURITY] [DSA 6566-1] expat security update
lists.debian.org - FIRST EPSSExploitation probabilityCVE-2026-76956
30-day exploitation probability 0.3%
first.org - OpenSSF OSV / OSV ScannerPackage advisoryDEBIAN-CVE-2026-76956osv.dev
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.