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 0.32% · 24.4th percentile
Risk Scores
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Ubuntu:Pro:20.04:LTS | rpm | 4.14.2.1+dfsg1-1, 0, 4.14.2.1+dfsg1-1ubuntu0.1~esm1 |
| Ubuntu:25.10 | rpm | 4.20.1+dfsg-1, *, * |
| Ubuntu:24.04:LTS | rpm | 4.18.0+dfsg-1build1, 4.18.0+dfsg-1build2, 4.18.2+dfsg-1 |
| Ubuntu:Pro:14.04:LTS | rpm | 4.11.1-3ubuntu0.1, 4.11.1-3, 4.11.1-2 |
| Ubuntu:Pro:16.04:LTS | rpm | *, 4.12.0.1+dfsg1-3ubuntu0.1~esm1, 4.12.0.1+dfsg1-3build2 |
| Ubuntu:22.04:LTS | rpm | *, 4.16.1.2+dfsg1-3ubuntu1, 4.16.1.2+dfsg1-3ubuntu3 |
| Ubuntu:Pro:18.04:LTS | rpm | 4.12.0.2+dfsg1-2build2, 4.14.0+dfsg1-2, 4.14.1+dfsg1-2 |
Timeline
- Jan 24, 2022 CVE Published
- Aug 23, 2022 EPSS Score
- Oct 8, 2022 EPSS Score
- Nov 23, 2022 EPSS Score
- Jan 7, 2023 EPSS Score
- Feb 22, 2023 EPSS Score
- Mar 7, 2023 EPSS Score
- Apr 9, 2023 EPSS Score
- May 25, 2023 EPSS Score
- Jul 10, 2023 EPSS Score
- Aug 25, 2023 EPSS Score
- Oct 9, 2023 EPSS Score
References
- https://ubuntu.com/security/CVE-2021-3521 third-party-advisory
- https://access.redhat.com/security/cve/CVE-2021-3521 third-party-advisory
- https://www.cve.org/CVERecord?id=CVE-2021-3521 third-party-advisory