Improper verification of vryptographic signature in rpm

1) Improper Verification of Cryptographic Signature

EUVDB-ID: #VU59993

Risk: Medium

CVSSv4.0: 6.9 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-3521

CWE-ID: CWE-347 - Improper Verification of Cryptographic Signature

Exploit availability: No

Description

The vulnerability allows a remote attacker to compromise the affected system.

The vulnerability exists due to an error in RPM's signature functionality, as RPM does not check the binding signature of subkeys before importing them. A remote attacker with ability to add malicious subkey to a legitimate public key can run malicious code on the system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

rpm: 4.0 - 4.17.0 rc1

CPE2.3

• cpe:2.3::rpm:rpm:4.0:*:*:*:*:*:*:*
• cpe:2.3::rpm:rpm:4.0.1:*:*:*:*:*:*:*
• cpe:2.3::rpm:rpm:4.0.2:*:*:*:*:*:*:*

External links

https://github.com/rpm-software-management/rpm/pull/1788
https://bugzilla.redhat.com/show_bug.cgi?id=1941098

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.