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TI-2026-22203 Aliases CVE-2026-27853GHSA-w68q-j3pw-29rg

Out-of-bounds write when rewriting large DNS packets

Priority LOW 33CWE-787Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-787 and the CVSS impact.

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00508 43rd percentileScored 2026-11-07
Fix Fixed DNSdist (PowerDNS): 1.9.12, 2.0.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
PowerDNSDNSdist1.9.0 to before 1.9.12; 2.0.0 to before 2.0.31.9.12, 2.0.3Patch availableCNA
  • DNSdist VendorPowerDNS Affected 1.9.0 to before 1.9.12; 2.0.0 to before 2.0.3 Fixed in 1.9.12, 2.0.3 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:powerdns:dnsdist:*:*:*:*:*:*:*:*1.9.0 to before 1.9.12; 2.0.0 to before 2.0.3VulnerablePowerDNS
  • cpe:2.3:a:powerdns:dnsdist:*:*:*:*:*:*:*:* Versions 1.9.0 to before 1.9.12; 2.0.0 to before 2.0.3 Vulnerable ·PowerDNS

Remediation

  • Fix · CNA DNSdist (PowerDNS) Fixed in 1.9.12, 2.0.3

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    PowerDNS DNSdist 1.9.12, 2.0.3

    7 records Highest priority Priority MEDIUM 2 MEDIUM, 5 LOW

    Other records, highest priority first

    • TI-2026-19357 Out-of-bounds read when parsing DNS packets via LuaPriority MEDIUM 44
    • TI-2026-19359 Unbounded memory allocation for DoQ and DoH3Priority MEDIUM 40
    • TI-2026-19358 DNS over HTTPS ACL bypassPriority LOW 34
    Show all 7 records →

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-27853
  2. 2026-10-03 Alias added: GHSA-w68q-j3pw-29rg
  3. 2026-10-25 EPSS moved to the below the 50th percentile

References

Advisory 1

  • TI-2026-19357 Out-of-bounds read when parsing DNS packets via Lua CVSS 3.1HIGH 8.2
  • TI-2026-25980 Out-of-bounds read in cache inspection via Lua CVSS 3.1CRITICAL 9.1
  • TI-2026-19359 Unbounded memory allocation for DoQ and DoH3 CVSS 3.1HIGH 7.5
  • TI-2017-05198 dnsdist version 1.1.0 is vulnerable to a flaw in authentication mechanism for REST API potentially allowing CSRF attack. CVSS 3.0HIGH 8.8
  • TI-2016-06076 Improper input validation in Open-Xchange GmbH dnsdist CVSS 3.0HIGH 7.5
  • TI-2026-25977 DoQ/DoH3 excessive memory allocation CVSS 3.1HIGH 7.5
See all 20 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences