CVE-2026-56408
Multiple security issues were discovered in expat, an XML parsing C library, including integer overflows, out-of-bounds write, NULL pointer dereferences, excessive resource consumption, and memory corruption through re-entrant parser API calls, which may result in denial of service or potentially the execution of arbitrary code. https://security-tracker.debian.org/tracker/DSA-6404-1
CSIRTS triage
- What
- Multiple security issues may result in denial of service or arbitrary code execution.
- Who is affected
- Users of Expat are affected.
- Urgency
- Remediation is necessary, but the vulnerabilities are not actively exploited.
- Action
- Users should apply the security update.
AI-assisted analysis generated from the source advisory — verify against the original.
⚡ Watch CVE-2026-56408
Get an email if CVE-2026-56408 is added to CISA KEV, gains public exploit code, or a new advisory cites it — max one per day, one-click unsubscribe.
Exploitation outlook
- Low exploitation risk0.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all EPSS-scored CVEs.
Advisory coverage (2)
- unknownDSA-6404-1 expat - security updatedebian · 2026-07-30
- medium[UPDATE] [medium] libexpat: Multiple vulnerabilities allow unspecified attackcert-bund · 2026-07-22
External references
Embed the live status
— this badge updates automatically when the KEV or exploit status changes. How to embed it →
[](https://www.csirts.com/cve/CVE-2026-56408)