[NEW] [medium] expat: Vulnerability Enables Denial of Service
An attacker can exploit a vulnerability in expat to perform a denial of service attack.
CSIRTS triage
- What
- An attacker can exploit a vulnerability to perform a denial-of-service attack.
- Who is affected
- Applications and systems using vulnerable expat library.
- Urgency
- Medium severity; standard update cycle appropriate.
- Action
- Update expat library to a patched version.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-2906
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-660460.68% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 49% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-66046 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
Recent advisories for expat
A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.
- highCVE-2026-66046: Expat through 2.8.3 contains a denial of service vulnerability caused by quadratic algorithmic…nvd · 2026-08-18
- medium[NEW] [medium] expat: Vulnerability enables denial of servicecert-bund · 2026-08-18
- highDSA-6446-1 expat - security updatedebian · 2026-08-18
- low[UPDATE] [low] expat: Vulnerability allows Denial of Servicecert-bund · 2026-08-06
- unknownDSA-6404-1 expat - security updatedebian · 2026-07-30
- medium[UPDATE] [medium] expat: Multiple vulnerabilitiescert-bund · 2026-07-22
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