Vulnerability in Rpm

CVE-2021-3521

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.

EPSS: 0.003 (23.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N.

Affected products

  • Rpm
  • N/a Rpm — versions Fixed in rpm-4.18.0-beta1, rpm-4.18.0-alpha2, rpm-4.18.0-alpha1 .

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-3521?
CVE-2021-3521 is a medium-severity vulnerability in Rpm, classified under Improper Verification of Cryptographic Signature. CVSS score: 4.7/10. Published 2022-08-22.
How severe is CVE-2021-3521?
Medium severity. CVSS v3 base score is 4.7 out of 10.
Is CVE-2021-3521 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.