#VU70042 NULL pointer dereference in Nokogiri - CVE-2022-23476

Vulnerability identifier: #VU70042

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2022-23476

CWE-ID: CWE-476

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Nokogiri
Universal components / Libraries / Programming Languages & Components

Vendor: nokogiri.org

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error within the Nokogiri::XML::Reader#attribute_hash method when parsing input returned from "xmlTextReaderExpand". A remote attacker can pass specially crafted XML input to the application and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Nokogiri: 1.13.8 - 1.13.9

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External links
https://github.com/sparklemotion/nokogiri/commit/9fe0761c47c0d4270d1a5220cfd25de080350d50
https://github.com/sparklemotion/nokogiri/commit/85410e38410f670cbbc8c5b00d07b843caee88ce
https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-qv4q-mr5r-qprj
https://github.com/sparklemotion/nokogiri/releases/tag/v1.13.10

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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.