Double Free in Putty

CVE-2026-48850

PuTTY 0.72 before 0.84 has a double free in RSA KEX.

Vulnerability class: Double Free

EPSS: 0.001 (17.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 3.7 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L.

Affected products

Putty — versions 0.72

Weakness classification (CWE)

CWE-415 — Double Free

References

cve@mitre.org (Release Notes)
cve@mitre.org (Patch, Vendor Advisory)

Frequently asked questions

What is CVE-2026-48850?: CVE-2026-48850 is a low-severity vulnerability in Putty, classified under Double Free. CVSS score: 3.7/10. Published 2026-05-25.
How severe is CVE-2026-48850?: Low severity. CVSS v3 base score is 3.7 out of 10.