Information disclosure in Symfony Twig

1) Information disclosure

EUVDB-ID: #VU73271

Risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2019-9942

CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor

Exploit availability: No

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to sandbox information disclosure via the __toString() method call on an object that even can be disabled by the security policy in place. A remote attacker can gain unauthorized access to sensitive information on the system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Twig: 1.0.0 - 2.6.2

CPE2.3

• cpe:2.3:a:symfony:twig:1.0.0:*:*:*:*:*:*:*
• cpe:2.3:a:symfony:twig:1.1.0:*:*:*:*:*:*:*
• cpe:2.3:a:symfony:twig:1.1.1:*:*:*:*:*:*:*
• cpe:2.3:a:symfony:twig:1.1.2:*:*:*:*:*:*:*
• cpe:2.3:a:symfony:twig:1.2.0:*:*:*:*:*:*:*
• cpe:2.3:a:symfony:twig:1.3.0:*:*:*:*:*:*:*
• cpe:2.3:a:symfony:twig:1.4.0:*:*:*:*:*:*:*
• cpe:2.3:a:symfony:twig:1.5.0:*:*:*:*:*:*:*
• cpe:2.3:a:symfony:twig:1.5.1:*:*:*:*:*:*:*
• cpe:2.3:a:symfony:twig:1.6.0:*:*:*:*:*:*:*

External links

https://symfony.com/blog/twig-sandbox-information-disclosure
https://github.com/twigphp/Twig/commit/eac5422956e1dcca89a3669a03a3ff32f0502077
https://www.debian.org/security/2019/dsa-4419
https://seclists.org/bugtraq/2019/Mar/60

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.