// For flags

CVE-2021-43173

Hanging RRDP request

Severity Score

7.5
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

In NLnet Labs Routinator prior to 0.10.2, a validation run can be delayed significantly by an RRDP repository by not answering but slowly drip-feeding bytes to keep the connection alive. This can be used to effectively stall validation. While Routinator has a configurable time-out value for RRDP connections, this time-out was only applied to individual read or write operations rather than the complete request. Thus, if an RRDP repository sends a little bit of data before that time-out expired, it can continuously extend the time it takes for the request to finish. Since validation will only continue once the update of an RRDP repository has concluded, this delay will cause validation to stall, leading to Routinator continuing to serve the old data set or, if in the initial validation run directly after starting, never serve any data at all.

En NLnet Labs Routinator versiones anteriores a 0.10.2, una ejecución de comprobación puede ser retrasada significativamente por un repositorio RRDP, no respondiendo sino alimentando lentamente con bytes para mantener viva la conexión. Esto puede ser usado para detener efectivamente la comprobación. Mientras que Routinator presenta un valor de tiempo de espera configurable para las conexiones RRDP, este tiempo de espera sólo se aplicaba a las operaciones individuales de lectura o escritura y no a la petición completa. Por lo tanto, si un repositorio RRDP envía un poco de datos antes de que el tiempo de espera expire, puede extender continuamente el tiempo que toma para que la petición termine. Dado que la comprobación sólo continuará una vez que la actualización de un repositorio RRDP haya concluido, este retraso causará que la comprobación se detenga, conllevando a que Routinator continúe sirviendo el antiguo conjunto de datos o, si en la comprobación inicial se ejecuta directamente después de comenzar, nunca sirva ningún dato

*Credits: We would like to thank Koen van Hove for the discovery.
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
Partial
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2021-11-01 CVE Reserved
  • 2021-11-09 CVE Published
  • 2024-09-16 CVE Updated
  • 2024-09-17 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-400: Uncontrolled Resource Consumption
  • CWE-755: Improper Handling of Exceptional Conditions
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Nlnetlabs
Search vendor "Nlnetlabs"
 Routinator
Search vendor "Nlnetlabs" for product "Routinator"
 < 0.10.2
Search vendor "Nlnetlabs" for product "Routinator" and version " < 0.10.2"
-
Affected
Debian
Search vendor "Debian"
 Debian Linux
Search vendor "Debian" for product "Debian Linux"
 11.0
Search vendor "Debian" for product "Debian Linux" and version "11.0"
-
Affected