libcURL up to 7.63.x lib/vauth/ntlm.c ntlm_decode_type2_target out-of-bounds

Summaryinfo

A vulnerability, which was classified as critical, has been found in libcURL up to 7.63.x. This impacts the function ntlm_decode_type2_target in the library lib/vauth/ntlm.c. This manipulation causes out-of-bounds. The identification of this vulnerability is CVE-2018-16890. It is possible to initiate the attack remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in libcURL up to 7.63.x (Network Utility Software). It has been declared as critical. Affected by this vulnerability is the function ntlm_decode_type2_target in the library lib/vauth/ntlm.c. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

libcurl versions from 7.36.0 to before 7.64.0 is vulnerable to a heap buffer out-of-bounds read. The function handling incoming NTLM type-2 messages (`lib/vauth/ntlm.c:ntlm_decode_type2_target`) does not validate incoming data correctly and is subject to an integer overflow vulnerability. Using that overflow, a malicious or broken NTLM server could trick libcurl to accept a bad length + offset combination that would lead to a buffer read out-of-bounds.

The bug was discovered 02/06/2019. The weakness was shared 02/06/2019 with Tencent as confirmed bug report (Bugzilla). It is possible to read the advisory at bugzilla.redhat.com. This vulnerability is known as CVE-2018-16890 since 09/11/2018. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit.

The commercial vulnerability scanner Qualys is able to test this issue with plugin 197366 (Ubuntu Security Notification for Curl Vulnerabilities (USN-3882-1)).

Upgrading to version 7.64.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at SecurityFocus (BID 106947†). The entries VDB-130618, VDB-130619, VDB-133589 and VDB-133491 are related to this item. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Network Utility Software

Name

• libcURL

Version

• 7.0
• 7.1
• 7.2
• 7.3
• 7.4
• 7.5
• 7.6
• 7.7
• 7.8
• 7.9
• 7.10
• 7.11
• 7.12
• 7.13
• 7.14
• 7.15
• 7.16
• 7.17
• 7.18
• 7.19
• 7.20
• 7.21
• 7.22
• 7.23
• 7.24
• 7.25
• 7.26
• 7.27
• 7.28
• 7.29
• 7.30
• 7.31
• 7.32
• 7.33
• 7.34
• 7.35
• 7.36
• 7.37
• 7.38
• 7.39
• 7.40
• 7.41
• 7.42
• 7.43
• 7.44
• 7.45
• 7.46
• 7.47
• 7.48
• 7.49
• 7.50
• 7.51
• 7.52
• 7.53
• 7.54
• 7.55
• 7.56
• 7.57
• 7.58
• 7.59
• 7.60
• 7.61
• 7.62
• 7.63

License

• open-source

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

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Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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