CVE-2026-43507 Denial of service in Prosody

What is CVE-2026-43507?

CVE-2026-43507 is a medium-severity denial of service vulnerability in Prosody, published on 1 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

An issue was discovered in Prosody before 0.12.6 and 1.0.0 through 13.0.0 before 13.0.5. A Denial of Service can occur via memory exhaustion caused by XML parsing resource amplification from unauthenticated connections.

Weakness: CWE-770

Which versions are affected by CVE-2026-43507?

It affects 1 product.

Products include Prosody Prosody.

How do I fix CVE-2026-43507?

Upgrade to a fixed version.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-43507 being exploited?

There is no known exploitation of CVE-2026-43507 in the wild and no public exploit code.

Other vulnerabilities in Prosody

• CVE-2014-2745 Denial of service in n/a High 7.8
• CVE-2022-0217 XML external entity in prosody High 7.5
• CVE-2021-37601 Information disclosure in n/a High 7.5
• CVE-2026-43504 Missing authorization in Prosody Medium 6.5
• CVE-2026-43505 Missing authorization in Prosody Medium 6.5

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2026-43507, GHSA-q9r3-wmh7-jgmq, UBUNTU-CVE-2026-43507.