PuTTY up to 0.70 Host Key Verification key management

Summaryinfo

A vulnerability identified as critical has been detected in PuTTY up to 0.70. This affects an unknown function of the component Host Key Verification. This manipulation causes key management. This vulnerability is registered as CVE-2019-9894. Remote exploitation of the attack is possible. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in PuTTY up to 0.70 (Connectivity Software). Affected by this vulnerability is some unknown functionality of the component Host Key Verification. The manipulation with an unknown input leads to a key management vulnerability. The CWE definition for the vulnerability is CWE-320. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A remotely triggerable memory overwrite in RSA key exchange in PuTTY before 0.71 can occur before host key verification.

The bug was discovered 03/16/2019. The weakness was published 03/21/2019 (Website). The advisory is shared at seclists.org. This vulnerability is known as CVE-2019-9894 since 03/20/2019. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1600.001 for this issue.

The vulnerability was handled as a non-public zero-day exploit for at least 5 days. During that time the estimated underground price was around $0-$5k. The commercial vulnerability scanner Qualys is able to test this issue with plugin 371709 (Putty Multiple Security Vulnerabilities).

Upgrading to version 0.71 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at SecurityFocus (BID 107523†). Similar entries are available at VDB-132086, VDB-132087, VDB-132088 and VDB-132089. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Connectivity Software

Name

• PuTTY

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5
• 0.6
• 0.7
• 0.8
• 0.9
• 0.10
• 0.11
• 0.12
• 0.13
• 0.14
• 0.15
• 0.16
• 0.17
• 0.18
• 0.19
• 0.20
• 0.21
• 0.22
• 0.23
• 0.24
• 0.25
• 0.26
• 0.27
• 0.28
• 0.29
• 0.30
• 0.31
• 0.32
• 0.33
• 0.34
• 0.35
• 0.36
• 0.37
• 0.38
• 0.39
• 0.40
• 0.41
• 0.42
• 0.43
• 0.44
• 0.45
• 0.46
• 0.47
• 0.48
• 0.49
• 0.50
• 0.51
• 0.52
• 0.53
• 0.54
• 0.55
• 0.56
• 0.57
• 0.58
• 0.59
• 0.60
• 0.61
• 0.62
• 0.63
• 0.64
• 0.65
• 0.66
• 0.67
• 0.68
• 0.69
• 0.70

License

• open-source

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

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Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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