CVE-2021-4239 (GCVE-0-2021-4239)

Vulnerability from cvelistv5 – Published: 2022-12-27 21:13 – Updated: 2025-04-14 16:59
VLAI
Title
Weak encryption and denial of service in github.com/flynn/noise
Summary
The Noise protocol implementation suffers from weakened cryptographic security after encrypting 2^64 messages, and a potential denial of service attack. After 2^64 (~18.4 quintillion) messages are encrypted with the Encrypt function, the nonce counter will wrap around, causing multiple messages to be encrypted with the same key and nonce. In a separate issue, the Decrypt function increments the nonce state even when it fails to decrypt a message. If an attacker can provide an invalid input to the Decrypt function, this will cause the nonce state to desynchronize between the peers, resulting in a failure to encrypt all subsequent messages.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE 400: Uncontrolled Resource Consumption
Assigner
Go
References
Impacted products
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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