[UPDATE] [medium] MIT Kerberos: Multiple vulnerabilities allow denial of service

mediumCVE-2026-40355 CVE-2026-40356

An attacker can exploit multiple vulnerabilities in MIT Kerberos to conduct a denial of service attack.

CSIRTS triage

vendor: MIT product: Kerberos Denial of service

What: Multiple vulnerabilities allow an attacker to conduct a denial of service attack.
Who is affected: Deployments of MIT Kerberos are affected.
Urgency: Remediation is medium urgency as denial of service attacks can disrupt services.
Action: Update to the latest version of MIT Kerberos.

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: 2026-09-01
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-2026-1290

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-2026-403550.61% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 47% of all EPSS-scored CVEs.
Low exploitation riskCVE-2026-403560.60% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 47% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-40355	coverage & exploitation status	NVD · CVE.org
CVE-2026-40356	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

unknownexploitedSiemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFPcisa
unknownUSN-8585-1: Kerberos vulnerabilitiesubuntu

Recent advisories for MIT Kerberos

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] MIT Kerberos: Vulnerability allows unspecified attackcert-bund · 2026-09-01
medium[UPDATE] [medium] MIT Kerberos: Multiple vulnerabilities allow Denial of Servicecert-bund · 2026-07-08