Input validation error in libxml2 (Alpine package)

1) Input validation error

EUVDB-ID: #VU32389

Risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2015-7941

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows context-dependent attackers to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input. A remote attacker can cause a denial of service (out-of-bounds read and libxml2 crash) via crafted XML data to the (1) xmlParseEntityDecl or (2) xmlParseConditionalSections function in parser.c, as demonstrated by non-terminated entities. "context dependent" seems to point to MiTM attack due to: If a user or automated system were tricked into opening a specially crafted document, an attacker could possibly cause libxml2 to crash, resulting in a denial of service.

Mitigation

Install update from vendor's website.

Vulnerable software versions

libxml2 (Alpine package): 2.9.1-r2 - 2.9.1-r3

CPE2.3

• cpe:2.3:o:alpine:libxml2_alpine_package:2.9.1-r2:*:*:*:*:alpine_linux:*:2.7
• cpe:2.3:o:alpine:libxml2_alpine_package:2.9.1-r3:*:*:*:*:alpine_linux:*:2.7

External links

https://git.alpinelinux.org/aports/commit/?id=0215e6588cf7cdc9ec3c57926af82e79b8366e46
https://git.alpinelinux.org/aports/commit/?id=9e3ec8396214f0ec09a2b5c75e65bbc808013c84
https://git.alpinelinux.org/aports/commit/?id=f084c470893c32a5ab1b765dfe1fa044af19320d
https://git.alpinelinux.org/aports/commit/?id=d43279c37e7c6a85eb14e2879d00bb7d74e9aa45

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.