What is CVE-2026-43507?

CVE-2026-43507 is a medium-severity vulnerability in Prosody, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 5.3/10. Published 2026-05-01.

How severe is CVE-2026-43507?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Resource exhaustion in Prosody

CVE-2026-43507

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.

Published 2026-05-01 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.006 (48.6th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 49th percentile — 48.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.006 · change: +0.003

Affected products

Prosody — versions 0, 1.0.0

Weakness classification (CWE)

CWE-770 — Allocation of Resources Without Limits or Throttling

References

www.openwall.com/lists/oss-security/2026/05/01/5 (Patch, Mailing List, Third Party Advisory)
prosody.im/security/advisory_735dd9d3/ (Patch, Mitigation, Vendor Advisory)
blog.unionium.org/ARTICLES/1.HTM (Third Party Advisory)

Frequently asked questions

What is CVE-2026-43507?: CVE-2026-43507 is a medium-severity vulnerability in Prosody, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 5.3/10. Published 2026-05-01.
How severe is CVE-2026-43507?: Medium severity. CVSS v3 base score is 5.3 out of 10.