Amazon Linux 2 : curl (ALAS-2018-951)

critical Nessus Plugin ID 109122

Synopsis

The remote Amazon Linux 2 host is missing a security update.

Description

HTTP authentication leak in redirects

libcurl might accidentally leak authentication data to third parties.
When asked to send custom headers in its HTTP requests, libcurl will send that set of headers first to the host in the initial URL but also, if asked to follow redirects and a 30X HTTP response code is returned, to the host mentioned in URL in the `Location:` response header value. Sending the same set of headers to subsequest hosts is in particular a problem for applications that pass on custom `Authorization:` headers, as this header often contains privacy sensitive information or data that could allow others to impersonate the libcurl-using client's request. (CVE-2018-1000007)

Out-of-bounds read in code handling HTTP/2 trailers

libcurl contains an out bounds read in code handling HTTP/2 trailers.
It was reported (https://github.com/curl/curl/pull/2231) that reading an HTTP/2 trailer could mess up future trailers since the stored size was one byte less than required. The problem is that the code that creates HTTP/1-like headers from the HTTP/2 trailer data once appended a string like `:` to the target buffer, while this was recently changed to `: ` (a space was added after the colon) but the following math wasn't updated correspondingly. When accessed, the data is read out of bounds and causes either a crash or that the (too large) data gets passed to client write. This could lead to a denial-of-service situation or an information disclosure if someone has a service that echoes back or uses the trailers for something. (CVE-2018-1000005)

Solution

Run 'yum update curl' to update your system.

See Also

https://alas.aws.amazon.com/AL2/ALAS-2018-951.html

Plugin Details

Severity: Critical

ID: 109122

File Name: al2_ALAS-2018-951.nasl

Version: 1.2

Type: local

Agent: unix

Published: 4/18/2018

Updated: 10/31/2024

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 6.4

Temporal Score: 4.7

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:P

CVSS Score Source: CVE-2018-1000005

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

CVSS Score Source: CVE-2018-1000007

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:libcurl, p-cpe:/a:amazon:linux:libcurl-devel, p-cpe:/a:amazon:linux:curl-debuginfo, cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:curl

Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 2/7/2018

Reference Information

CVE: CVE-2018-1000005, CVE-2018-1000007

ALAS: 2018-951