Vulnerability identifier: #VU71992

Vulnerability risk: High

CVSSv3.1: 7.9 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-0286

CWE-ID: CWE-843

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
OpenSSL
Server applications / Encryption software

Vendor: OpenSSL Software Foundation

Description

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

The vulnerability exists due to a type confusion error related to X.400 address processing inside an X.509 GeneralName. A remote attacker can pass specially crafted data to the application, trigger a type confusion error and perform a denial of service (DoS) attack or read memory contents.

In most cases, the attack requires the attacker to provide both the certificate chain and CRL, neither of which need to have a valid signature. If the attacker only controls one of these inputs, the other input must already contain an X.400 address as a CRL distribution point, which is uncommon. As such, this vulnerability is most likely to only affect applications which have implemented their own functionality for retrieving CRLs over a network.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

OpenSSL: 3.0.0 - 3.0.7, 1.1.1 - 1.1.1s, 1.0.2 - 1.0.2zf, 1.1.0 - 1.1.0l, 1.0.0 - 1.0.0t, 1.0.1 - 1.0.1u

---

External links
http://www.openssl.org/news/secadv/20230207.txt

---

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.