CVE-2026-115506 (GCVE-0-2026-115506)

Vulnerability from cvelistv5 – Published: 2026-10-22 19:14 – Updated: 2026-10-22 19:14
VLAI
Title
libexpat through 2.9.0 Denial of Service via Billion Laughs Detection Delay
Summary
libexpat through 2.9.0 contains a denial of service vulnerability because billion laughs protection in accountingDiffTolerated() in xmlparse.c detects entity amplification too late. Attackers can supply a moderately sized XML document with a large DTD and nested entity expansions to consume tens of seconds of CPU per parse.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-776 - Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion')
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6762 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
libexpat libexpat Affected: 0 , ≤ 2.9.0 (semver)
    cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-10-22 00:00
Credits
Hanno Böck Shani Yosef
Show details on NVD website
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    "datePublished": "2026-10-22T19:14:06.001Z",
    "dateReserved": "2026-10-22T16:14:59.466Z",
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          }
        ],
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}



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