ALAS-2020-1375


Amazon Linux AMI Security Advisory: ALAS-2020-1375
Advisory Release Date: 2020-05-22 20:58 Pacific
Advisory Updated Date: 2020-08-31 21:52 Pacific
Severity: Medium

Issue Overview:

http.cookiejar.DefaultPolicy.domain_return_ok in Lib/http/cookiejar.py in Python before 3.7.3 does not correctly validate the domain: it can be tricked into sending existing cookies to the wrong server. An attacker may abuse this flaw by using a server with a hostname that has another valid hostname as a suffix (e.g., pythonicexample.com to steal cookies for example.com). When a program uses http.cookiejar.DefaultPolicy and tries to do an HTTP connection to an attacker-controlled server, existing cookies can be leaked to the attacker. This affects 2.x through 2.7.16, 3.x before 3.4.10, 3.5.x before 3.5.7, 3.6.x before 3.6.9, and 3.7.x before 3.7.3.(CVE-2018-20852 )

An issue was discovered in urllib2 in Python 2.x through 2.7.17 and urllib in Python 3.x through 3.8.0. CRLF injection is possible if the attacker controls a url parameter, as demonstrated by the first argument to urllib.request.urlopen with \r\n (specifically in the host component of a URL) followed by an HTTP header. This is similar to the CVE-2019-9740 query string issue and the CVE-2019-9947 path string issue. (This is not exploitable when glibc has CVE-2016-10739 fixed.) A CRLF injection flaw was discovered in python in the way URLs are handled when doing an HTTP/HTTPS connection (e.g. through urlopen() or HTTPConnection). An attacker who can control the url parameter passed to urlopen method in the urllib/urllib2 modules can inject CRLF sequences and HTTP headers by abusing the "host" part of the URL. (CVE-2019-18348 )
(Additional CVE details added after release.)


Affected Packages:

python27


Issue Correction:
Run yum update python27 to update your system.

New Packages:
i686:
    python27-devel-2.7.18-1.137.amzn1.i686
    python27-libs-2.7.18-1.137.amzn1.i686
    python27-test-2.7.18-1.137.amzn1.i686
    python27-tools-2.7.18-1.137.amzn1.i686
    python27-2.7.18-1.137.amzn1.i686
    python27-debuginfo-2.7.18-1.137.amzn1.i686

src:
    python27-2.7.18-1.137.amzn1.src

x86_64:
    python27-devel-2.7.18-1.137.amzn1.x86_64
    python27-debuginfo-2.7.18-1.137.amzn1.x86_64
    python27-2.7.18-1.137.amzn1.x86_64
    python27-tools-2.7.18-1.137.amzn1.x86_64
    python27-test-2.7.18-1.137.amzn1.x86_64
    python27-libs-2.7.18-1.137.amzn1.x86_64