#VU51939 Input validation error in Apache CXF - CVE-2021-22696

Vulnerability identifier: #VU51939

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-2021-22696

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Apache CXF
Server applications / Frameworks for developing and running applications

Vendor: Apache Foundation

Description

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

The vulnerability exists due to improper validation of "request_uri" parameter by the OAuth 2 authorization service. A remote attacker can pass specially crafted input to the application and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Apache CXF: 3.3.0 - 3.4.2

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External links
https://www.openwall.com/lists/oss-security/2021/04/02/2
https://cxf.apache.org/security-advisories.data/CVE-2021-22696.txt.asc
https://lists.apache.org/thread.html/r6445001cc5f9a2bb1e6316993753306e054bdd1d702656b7cbe59045@%3Cannounce.apache.org%3E
https://lists.apache.org/thread.html/r8651c06212c56294a1c0ea61a5ad7790c06502209c03f05c0c7c9914@%3Cdev.cxf.apache.org%3E
https://lists.apache.org/thread.html/r8651c06212c56294a1c0ea61a5ad7790c06502209c03f05c0c7c9914@%3Cusers.cxf.apache.org%3E
https://lists.apache.org/thread.html/rec7160382badd3ef4ad017a22f64a266c7188b9ba71394f0d321e2d4@%3Ccommits.cxf.apache.org%3E

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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.