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CVE-2026-27853 (GCVE-0-2026-27853)

Vulnerability from cvelistv5 – Published: 2026-03-31 12:04 – Updated: 2026-03-31 13:17
VLAI
Title
Out-of-bounds write when rewriting large DNS packets
Summary
An attacker might be able to trigger an out-of-bounds write by sending crafted DNS responses to a DNSdist using the DNSQuestion:changeName or DNSResponse:changeName methods in custom Lua code. In some cases the rewritten packet might become larger than the initial response and even exceed 65535 bytes, potentially leading to a crash resulting in denial of service.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-31 13:14 UTC
CWE
  • Out-of-bounds Write
  • CWE-787 - Out-of-bounds Write
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
ilya rozentsvaig
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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