Amazon Linux AMI update for python-lxml

Published: 2023-03-23

Risk	Medium
Patch available	YES
Number of vulnerabilities	2
CVE-ID	CVE-2020-27783 CVE-2021-43818
CWE-ID	CWE-79
Exploitation vector	Network
Public exploit	N/A
Vulnerable software	Amazon Linux AMI Operating systems & Components / Operating system python-lxml Operating systems & Components / Operating system package or component
Vendor	Amazon Web Services

Security Bulletin

This security bulletin contains information about 2 vulnerabilities.

1) Cross-site scripting

EUVDB-ID: #VU48793

Risk: Medium

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-27783

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Exploit availability: No

Description

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data within lxml Python clean module. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

Mitigation

Update the affected packages:

i686:
    python-lxml-debuginfo-3.2.1-4.10.amzn1.i686
    python26-lxml-3.2.1-4.10.amzn1.i686
    python27-lxml-3.2.1-4.10.amzn1.i686

noarch:
    python26-lxml-docs-3.2.1-4.10.amzn1.noarch
    python27-lxml-docs-3.2.1-4.10.amzn1.noarch

src:
    python-lxml-3.2.1-4.10.amzn1.src

x86_64:
    python-lxml-debuginfo-3.2.1-4.10.amzn1.x86_64
    python26-lxml-3.2.1-4.10.amzn1.x86_64
    python27-lxml-3.2.1-4.10.amzn1.x86_64

Vulnerable software versions

Amazon Linux AMI: All versions

python-lxml: before 3.2.1-4.10

CPE2.3

External links

https://alas.aws.amazon.com/ALAS-2023-1709.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) Cross-site scripting

EUVDB-ID: #VU59660

Risk: Low

CVSSv4.0: 1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-43818