CVE-2019-3822

Published Feb 6, 2019

Last updated a year ago

Overview

Description
libcurl versions from 7.36.0 to before 7.64.0 are vulnerable to a stack-based buffer overflow. The function creating an outgoing NTLM type-3 header (`lib/vauth/ntlm.c:Curl_auth_create_ntlm_type3_message()`), generates the request HTTP header contents based on previously received data. The check that exists to prevent the local buffer from getting overflowed is implemented wrongly (using unsigned math) and as such it does not prevent the overflow from happening. This output data can grow larger than the local buffer if very large 'nt response' data is extracted from a previous NTLMv2 header provided by the malicious or broken HTTP server. Such a 'large value' needs to be around 1000 bytes or more. The actual payload data copied to the target buffer comes from the NTLMv2 type-2 response header.
Source
secalert@redhat.com
NVD status
Modified

Risk scores

CVSS 3.1

Type
Primary
Base score
9.8
Impact score
5.9
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity
CRITICAL

CVSS 3.0

Type
Secondary
Base score
7.1
Impact score
4.2
Exploitability score
2.8
Vector string
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
Severity
HIGH

CVSS 2.0

Type
Primary
Base score
7.5
Impact score
6.4
Exploitability score
10
Vector string
AV:N/AC:L/Au:N/C:P/I:P/A:P

Weaknesses

nvd@nist.gov
CWE-787
secalert@redhat.com
CWE-121

Social media

Hype score
Not currently trending

Configurations