CVE-2026-48850: Putty double free vulnerability

Putty · Putty

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

5.9 CVSS 3.1 Medium EPSS 0.41% · top 67.1% CWE-415 · Double free

5.9CVSS 3.1 base score

0.41%EPSS exploitation probability, 30 days

NoNot in CISA KEV

1Affected product versions listed by NVD

2References

24 Jul 2026Last modified by NVD

Description

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

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

Putty Putty

References

Link	Tags
https://lists.tartarus.org/pipermail/putty-announce/2026/000042.html	Release Notes
https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/rsakex-double-free.html	PatchVendor Advisory

Track CVE-2026-48850 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-48850), CISA KEV, FIRST EPSS (scores of 2026-09-29). This page is refreshed as NVD updates the record.