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CVE-2026-27854 (GCVE-0-2026-27854)

Vulnerability from cvelistv5 – Published: 2026-03-31 12:06 – Updated: 2026-04-02 13:46
VLAI
Title
Use after free when parsing EDNS options in Lua
Summary
An attacker might be able to trigger a use-after-free by sending crafted DNS queries to a DNSdist using the DNSQuestion:getEDNSOptions method in custom Lua code. In some cases DNSQuestion:getEDNSOptions might refer to a version of the DNS packet that has been modified, thus triggering a use-after-free and potentially a crash resulting in denial of service.
Severity
4.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-31 13:12 UTC
CWE
  • Use After Free
  • CWE-416 - Use After Free
Assigner
References
Impacted products
Vendor Product Version CPE status
PowerDNS DNSdist Affected: 1.9.0 , < 1.9.12 (semver)
Affected: 2.0.0 , < 2.0.3 (semver)
guessed Create a notification for this product.
Date Public
2026-03-30 22:00
Credits
Naoki Wakamatsu
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.

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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.


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