Review reviewHigh

CVE-2026-27854

PowerDNS DNSdist, dnsdist

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.

CVSS
7.5
EPSS
0.47%
38.3% percentile
CISA KEV
Not listed
Published
2026.03.31
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability0.47%
Technical severityCVSS 7.5

Vulnerability overview

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.

Affected product and versions

Product
PowerDNS DNSdist, dnsdist
Affected versions
>= 1.9.0 < 1.9.12, >= 2.0.0 < 2.0.3
Fixed versions
1.9.12, 2.0.3

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that PowerDNS DNSdist, dnsdist and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
CWE-416