Multiple vulnerabilities in Apache Tomcat (June 30, 2026)

unknownpublic exploitCVE-2026-55276 CVE-2026-50229 CVE-2026-55956 CVE-2026-55955 CVE-2026-53434 CVE-2026-53404

Multiple vulnerabilities have been discovered in Apache Tomcat. Some of them allow an attacker to cause remote indirect code injection (XSS), security policy bypass, and an unspecified security issue by the vendor.

CSIRTS triage

vendor: Apache product: Tomcat Remote code executionOther

What: Multiple vulnerabilities allow an attacker to cause remote indirect code injection, security policy bypass, and an unspecified security issue.
Who is affected: Deployments of Apache Tomcat are affected.
Urgency: Remediation is urgent due to the potential for exploitation, although the severity is currently unknown.
Action: Users should apply the necessary updates as soon as they are available.

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

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Details

Source: CERT-FR Avis de sécurité (FR · national-cert · site)
Severity: unknown
Published: 2026-06-30
Exploitation: Not in CISA KEV at last sync
Language: Machine-translated to English — verify against the original

Original advisory: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-0817/

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-2026-552760.37% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 29% of all scored CVEs.
Low exploitation riskCVE-2026-502290.42% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 34% of all scored CVEs.
Low exploitation riskCVE-2026-559560.41% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 33% of all scored CVEs.
Low exploitation riskCVE-2026-559550.28% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 20% of all scored CVEs.
Low exploitation riskCVE-2026-534340.37% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 29% of all scored CVEs.
Low exploitation riskCVE-2026-534040.41% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 33% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-55276	coverage & exploitation status	NVD · CVE.org
CVE-2026-50229	coverage & exploitation status	NVD · CVE.org
CVE-2026-55956	coverage & exploitation status	NVD · CVE.org
CVE-2026-55955	coverage & exploitation status	NVD · CVE.org
CVE-2026-53434	coverage & exploitation status	NVD · CVE.org
CVE-2026-53404	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.

medium[UPDATE] [medium] Apache Tomcat and Tomcat Native: Multiple vulnerabilitiescert-bund · 2026-07-10
medium[UPDATE] [medium] Apache Tomcat: Multiple vulnerabilitiescert-bund · 2026-07-09
high[UPDATE] [high] Apache Tomcat: Multiple vulnerabilitiescert-bund · 2026-07-02
unknownApache Tomcat Multiple Vulnerabilitieshkcert · 2026-07-02
highCVE-2026-55957: Missing Critical Step in Authentication vulnerability in Apache Tomcat when the JNDIRealm was …nvd · 2026-06-29
mediumCVE-2026-55956: Improper Authorization vulnerability in Apache Tomcat leads to security constraints specified …nvd · 2026-06-29