// For flags

CVE-2021-3521

rpm: RPM does not require subkeys to have a valid binding signature

Severity Score

4.7
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

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.

Se presenta un fallo en la funcionalidad de firma de RPM. Las subclaves OpenPGP se asocian a una clave primaria por medio de una "firma vinculante". RPM no comprueba la firma vinculante de las subclaves antes de importarlas. Si un atacante es capaz de añadir o hacer ingeniería social para que otra parte añada una subclave maliciosa a una clave pública legítima, RPM podría confiar erróneamente en una firma maliciosa. El mayor impacto de este fallo es la integridad de los datos. Para explotar este fallo, un atacante debe comprometer un repositorio de RPM o convencer a un administrador para que instale un RPM o una clave pública que no sean confiables. Es recomendado encarecidamente usar sólo RPMs y claves públicas de fuentes confiables.

There is a flaw in RPM's signature functionality. OpenPGP subkeys are associated with a primary key via a "binding signature."[1] 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.

1. https://tools.ietf.org/html/rfc4880#section-5.2.1

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
High
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None
Attack Vector
Local
Attack Complexity
High
Privileges Required
Low
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2021-04-28 CVE Reserved
  • 2022-01-25 CVE Published
  • 2024-02-02 EPSS Updated
  • 2024-08-03 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-347: Improper Verification of Cryptographic Signature
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Rpm
Search vendor "Rpm"
Rpm
Search vendor "Rpm" for product "Rpm"
< 4.17.1
Search vendor "Rpm" for product "Rpm" and version " < 4.17.1"
-
Affected