PT-2026-43122 · Putty+1 · Putty+1

Sgtatham + 1 · CVE-2026-48850 · Published 2026-05-22 · Updated 2026-07-24

Positive Technologies (AI Summary)

CVSS v3.1

5.9

Medium

Base vector

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

Name of the Vulnerable Software and Affected Versions PuTTY versions 0.72 through 0.83

Description A double free issue exists in the RSA KEX (Key Exchange), which is the process used by two parties to establish a shared secret key over an insecure channel.

Recommendations Update to version 0.84.

Fix

DoS

Double Free

Weakness Enumeration

CWE-415

Related Identifiers

BDU:2026-07828

CVE-2026-48850

Affected Products

Putty

Red Os

References · 15

• https://security-tracker.debian.org/tracker/CVE-2026-48850 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-48850 · Security Note
• https://bdu.fstec.ru/vul/2026-07828 · Security Note
• https://ubuntu.com/security/CVE-2026-48850 · Vendor Advisory
• http://repo.red-soft.ru/redos/8.0/x86_64/updates · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-48850 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-48850 · Vendor Advisory
• https://chiark.greenend.org.uk/~sgtatham/putty/wishlist/rsakex-double-free.html · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-48850 · Security Note
• https://t.me/cveNotify/164910 · Telegram Post
• https://redos.red-soft.ru/support/secure/uyazvimosti/support/secure/uyazvimosti/uyazvimost-putty-cve-2026-48850-7.3 · Note
• https://t.me/cveNotify/219891 · Telegram Post
• https://lists.tartarus.org/pipermail/putty-announce/2026/000042.html · Note
• https://twitter.com/threatcluster/status/2064570914361004233 · Twitter Post
• https://redos.red-soft.ru/support/secure/uyazvimosti/support/secure/uyazvimosti-red-os-8-0/uyazvimost-putty-cve-2026-48850-8.0 · Note