NULL pointer dereference in Mutt

CVE-2026-43864

mutt before 2.3.2 has a show_sig_summary NULL pointer dereference.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 2.5 (Low). Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.001 (1.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 2nd percentile — 1.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-43864: held from 0.001 to 0.001.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-43864?
CVE-2026-43864 is a low-severity vulnerability in Mutt, classified under NULL Pointer Dereference. CVSS score: 2.5/10. Published 2026-05-04.
How severe is CVE-2026-43864?
Low severity. CVSS v3 base score is 2.5 out of 10.