CVE-2026-76956

HIGHPre-NVD 5.97.5▲
EchelonGraph scoreMEDIUM confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-08-20. a secondary CVSS source baseline 5.9; sources differ by 1.6.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
7.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.9Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
5.9
EG Score
7.5(medium)
EG Risk
49(Track)
EG Risk 49/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity75% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
18%
KEV
Not listed

Published

August 20, 2026

Last Modified

August 20, 2026

Advisory Details (1)

Auto-updated Aug 20, 2026
No patch confirmed yet. Sources: github_pr.
github_pr

[CVE-REQUESTED] lib: Fix inverted `getentropy()` return in `writeRandomBytes_getentropy`

Upstream fix in progress (PR #1326 · libexpat/libexpat, state=open)

https://github.com/libexpat/libexpat/pull/1326

Vendor Advisories for CVE-2026-76956(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 16× in last 7d / 16× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-21 05:18 UTCEG score recompute
  2. 2026-08-21 05:18 UTCGHSA enrichment
  3. 2026-08-20 22:56 UTCEPSS rescore
  4. 2026-08-20 18:17 UTCEG score recompute
  5. 2026-08-20 18:17 UTCGHSA enrichment
  6. 2026-08-20 17:57 UTCGHSA enrichment
  7. 2026-08-20 17:32 UTCEG score recompute
  8. 2026-08-20 17:32 UTCGHSA enrichment
  9. 2026-08-20 17:31 UTCMITRE cvelistV5CVSS v3 → 5.9 · severity → MEDIUM
  10. 2026-08-20 16:34 UTCEG score recompute
  11. 2026-08-20 16:34 UTCGHSA enrichment
  12. 2026-08-20 15:45 UTCEG score recompute
  13. 2026-08-20 15:45 UTCGHSA enrichment
  14. 2026-08-20 05:20 UTCEG score recompute
  15. 2026-08-20 04:38 UTCEG score recompute
  16. 2026-08-20 04:37 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-76956?
CVE-2026-76956 is a high vulnerability published on August 20, 2026. 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.
When was CVE-2026-76956 disclosed?
CVE-2026-76956 was first published in the National Vulnerability Database on August 20, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-76956 actively exploited?
CVE-2026-76956 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 81.7% of all scored CVEs.
What is the CVSS score of CVE-2026-76956?
CVE-2026-76956 has a CVSS v3 base score of 5.9 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 7.5.
How do I remediate CVE-2026-76956?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-76956, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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