RPM OpenPGP Key rpmio/rpmpgp.c signature verification

Summaryinfo

A vulnerability marked as problematic has been reported in RPM. This affects an unknown part of the file rpmio/rpmpgp.c of the component OpenPGP Key Handler. The manipulation leads to signature verification. This vulnerability is referenced as CVE-2021-3521. Remote exploitation of the attack is possible. No exploit is available. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability was found in RPM (the affected version is unknown). It has been rated as problematic. This issue affects an unknown code of the file rpmio/rpmpgp.c of the component OpenPGP Key Handler. The manipulation with an unknown input leads to a signature verification vulnerability. Using CWE to declare the problem leads to CWE-347. The product does not verify, or incorrectly verifies, the cryptographic signature for data. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

There is a flaw in RPM's signature functionality. OpenPGP subkeys are associated with a primary key via a "binding signature." RPM does not check the binding signature of subkeys prior to importing them. If an attacker is able to add or socially engineer another party to add a malicious subkey to a legitimate public key, RPM could wrongly trust a malicious signature. The greatest impact of this flaw is to data integrity. To exploit this flaw, an attacker must either compromise an RPM repository or convince an administrator to install an untrusted RPM or public key. It is strongly recommended to only use RPMs and public keys from trusted sources.

The weakness was published 08/23/2022. The advisory is shared at github.com. The identification of this vulnerability is CVE-2021-3521 since 04/28/2021. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 236682 (Alibaba Cloud Linux 3 : 0007: rpm (ALINUX3-SA-2022:0007)), which helps to determine the existence of the flaw in a target environment.

Applying the patch bd36c5dc9fb6d90c46fbfed8c2d67516fc571ec8 is able to eliminate this problem. The bugfix is ready for download at github.com.

The vulnerability is also documented in the vulnerability database at Tenable (236682). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• RPM

License

• open-source

CPE 2.3info

• 🔍

CPE 2.2info

• 🔍

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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