[NEW] [medium] Apache Tomcat: Vulnerability allows Denial of Service

mediumCVE-2026-66299

A remote, anonymous attacker can exploit a vulnerability in Apache Tomcat to conduct a Denial of Service attack.

CSIRTS triage

vendor: Apache product: Tomcat Denial of service

What: A vulnerability in Apache Tomcat allows remote anonymous attackers to conduct a Denial of Service attack.
Who is affected: Deployments of Apache Tomcat are affected.
Urgency: Remediation is medium urgency as the vulnerability could lead to service disruption.
Action: Apply available patches or implement mitigations.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: CERT-Bund (BSI) Security Advisories (DE · national-cert · site)
Severity: medium
Published: 2026-07-29
Exploitation: Not in CISA KEV at last sync
Language: Machine-translated to English — verify against the original

Original advisory: https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-2571

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-2026-662990.31% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 23% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-66299	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 Apache Tomcat

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.

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