Vulnerability identifier: #VU61391

Vulnerability risk: Medium

CVSSv3.1: 6.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2022-0778

CWE-ID: CWE-835

Exploitation vector: Network

Exploit availability: Yes

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 infinite loop within the BN_mod_sqrt() function when processing an ASN.1 certificate that contains elliptic curve public keys in compressed form or explicit elliptic curve parameters with a base point encoded in compressed form. A remote attacker can supply a specially crafted certificate to the TLS server or client, consume all available system resources and cause denial of service conditions.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

OpenSSL: 3.0.0 - 3.0.1, 1.1.1 - 1.1.1m, 1.0.2 - 1.0.2zc, 1.0.1 - 1.0.1u, 1.0.0 - 1.0.0t

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External links
http://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=380085481c64de749a6dd25cdf0bcf4360b30f83
http://www.openssl.org/news/secadv/20220315.txt
http://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=a466912611aa6cbdf550cd10601390e587451246
http://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=3118eb64934499d93db3230748a452351d1d9a65

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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. However, proof of concept for this vulnerability is available.