CVE-2021-36367

PuTTY through 0.75 proceeds with establishing an SSH session even if it has never sent a substantive authentication response. This makes it easier for an attacker-controlled SSH server to present a later spoofed authentication prompt (that the attacker can use to capture credential data, and use that data for purposes that are undesired by the client user).

CVSS v3 8.1 HIGH
CVSS v2.0 5.8 MEDIUM

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

5.8^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:M/Au:N/C:P/I:P/A:N

Exploitability : 8.6 / Impact : 4.9

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact NONE

References

Link	Resource
https://git.tartarus.org/?p=simon/putty.git%3Ba=commit%3Bh=1dc5659aa62848f0aeb5de7bd3839fecc7debefa
https://lists.debian.org/debian-lts-announce/2024/04/msg00016.html
https://www.chiark.greenend.org.uk/~sgtatham/putty/changes.html	Release Notes Third Party Advisory
https://www.debian.org/security/2023/dsa-5588

Configurations

Configuration 1 (hide)

cpe:2.3:a:putty:putty:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2021-07-09 21:15

Updated : 2024-07-03 01:36

NVD link : CVE-2021-36367

Mitre link : CVE-2021-36367

CVE.ORG link : CVE-2021-36367

JSON object : View

Products Affected

putty

putty

CWE

CWE-345

Insufficient Verification of Data Authenticity

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