PatchTheCVECVE-2026-15561: A flaw was found in EAP's undertow http/1.1 chunked-transfer decoder
CVE-2026-15561 is a high-severity flaw (CVSS 7.5) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
A flaw was found in EAP's undertow http/1.1 chunked-transfer decoder. missing limits on size and count would allow an attacker to use an unauthenticated connection to drive the JVM to an OutOfMemory error, stopping all deployments on the listener, and achieving Denial of Service.
Why this priority
- High severity
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 7.5 (High) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.5% (top 61%) |
| CISA exploited list | No |
| Weakness | CWE-770 |
| Published | 2026-08-11 |
| Last modified | 2026-10-22 |
Timeline
- Published CVE record published
- Updated Record last modified
Exact fixes by distribution
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-15561?
No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.
Is CVE-2026-15561 being exploited?
CVE-2026-15561 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-15561 affect?
CVE-2026-15561 affects affected software. Severity is high (CVSS 7.5). A flaw was found in EAP's undertow http/1.1 chunked-transfer decoder. missing limits on size and count would allow an attacker to use an unauthenticated connection to drive the JVM to an OutOfMemory error, stopping all deployments on the li
How urgent is CVE-2026-15561?
Priority 41/100. High severity; Remotely exploitable, no login, no user action