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CVE-2025-40779 (GCVE-0-2025-40779)

Vulnerability from cvelistv5 – Published: 2025-08-27 20:23 – Updated: 2025-11-04 21:10
VLAI
Title
Kea crash upon interaction between specific client options and subnet selection
Summary
If a DHCPv4 client sends a request with some specific options, and Kea fails to find an appropriate subnet for the client, the `kea-dhcp4` process will abort with an assertion failure. This happens only if the client request is unicast directly to Kea; broadcast messages do not cause the problem. This issue affects Kea versions 2.7.1 through 2.7.9, 3.0.0, and 3.1.0.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-08-28 14:07 UTC
CWE
  • CWE-476 - NULL Pointer Dereference
Assigner
References
Impacted products
Vendor Product Version CPE status
ISC Kea Affected: 2.7.1 , ≤ 2.7.9 (custom)
Affected: 3.0.0
Affected: 3.1.0
Unaffected: 2.6.0 , ≤ 2.6.4 (custom)
guessed Create a notification for this product.
Date Public
2025-08-27 00:00
Credits
ISC would like to thank the following for bringing this vulnerability to our attention: * Jochen M. * Martin Dinev, Trading212 * Ashwani Kumar, Post Graduate Institute of Medical Education & Research, Chandigarh, India * Bret Giddings, University of Essex * Florian Ritterhoff, Munich University of Applied Sciences
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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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • 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.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.