Every CVE Search/ Get API key

CVE-2026-40210

Out-of-bounds read in SetMacAddrAction

4.8 MediumFix available

An out-of-bounds read might happen when SetMacAddrAction is used, potentially resulting in uninitialized memory being sent over the network or a crash.

Attack profile

How easy it is to exploit

Attack vector
Network
Complexity
High
Privileges needed
None
User interaction
None

What an attacker can affect

Confidentiality
Low
Integrity
None
Availability
Low

Exploit likelihood

0.74%Up 0.4 points since Jun 26, 2026
90%50%10%1%

What each source reports

CVE List Score used 4.8

Out-of-bounds read in SetMacAddrAction

An out-of-bounds read might happen when SetMacAddrAction is used, potentially resulting in uninitialized memory being sent over the network or a crash.

Record
CVE-2026-40210
CVSS 3.1
4.8 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Weakness
CWE-126
Updated
2026-11-02
EUVDEUVD-2026-39349 4.8

An out-of-bounds read might happen when SetMacAddrAction is used, potentially resulting in uninitialized memory being sent over the network or a crash.

Record
EUVD-2026-39349
CVSS 3.1
4.8 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Updated
2026-11-02
GitHub AdvisoriesGHSA-5292-qc6p-vf38 4.8

An out-of-bounds read might happen when SetMacAddrAction is used, potentially resulting in...

An out-of-bounds read might happen when SetMacAddrAction is used, potentially resulting in uninitialized memory being sent over the network or a crash.

Record
GHSA-5292-qc6p-vf38
CVSS 3.1
4.8 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Weakness
CWE-126
Updated
2026-11-02
NVD 4.8

An out-of-bounds read might happen when SetMacAddrAction is used, potentially resulting in uninitialized memory being sent over the network or a crash.

Record
CVE-2026-40210
CVSS 3.1
4.8 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Weakness
CWE-126
Updated
2026-11-02
OSV 4.8

Out-of-bounds read in SetMacAddrAction

An out-of-bounds read might happen when SetMacAddrAction is used, potentially resulting in uninitialized memory being sent over the network or a crash.

Record
CVE-2026-40210
CVSS 3.1
4.8 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Updated
2026-11-02
OSVDEBIAN-CVE-2026-40210 4.8

An out-of-bounds read might happen when SetMacAddrAction is used, potentially resulting in uninitialized memory being sent over the network or a crash.

Record
DEBIAN-CVE-2026-40210
CVSS 3.1
4.8 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Updated
2026-11-02
Show 5 moreShow less
OSVUBUNTU-CVE-2026-40210 4.8

An out-of-bounds read might happen when SetMacAddrAction is used, potentially resulting in uninitialized memory being sent over the network or a crash.

Record
UBUNTU-CVE-2026-40210
CVSS 3.1
4.8 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Updated
2026-11-02
OSVopenSUSE-SU-2026:11411-1 No score

dnsdist-2.0.7-1.1 on GA media

These are all security issues fixed in the dnsdist-2.0.7-1.1 package on the GA media of openSUSE Tumbleweed.

Record
openSUSE-SU-2026:11411-1
Updated
2026-11-02
OSVopenSUSE-SU-2026:21533-1 No score

Security update for dnsdist

This update for dnsdist fixes the following issues:

Update to 1.9.15.

Changes for dnsdist:

Security issues fixed:

  • CVE-2026-40011: invalid output produced in the prometheus endpoint when a large number of crafted DNS queries are sent (bsc#1269204).
  • CVE-2026-40208: processing of DoH3 queries can be delayed via DoH3 GET queries with an invalid DATA frames (bsc#1269207).
  • CVE-2026-40209: outgoing TCP connections to backend can get stuck until a timeout occurs when specially crafted IXFR queries are sent (bsc#1269206).
  • CVE-2026-40210: out-of-bounds read when SetMacAddrAction is used can lead to uninitialized memory being sent over the network or a crash (bsc#1269205).
  • CVE-2026-40211: crafted DNS over HTTP/3 queries can trigger an exception that prevents memory from being freed and can lead to an OOM condition (bsc#1269203).
  • CVE-2026-42004: crafted EDNS OPT record will be ignored by filtering rules, but will be rewritten as a valid OPT record when EDNS Client Subnet is inserted (bsc#1269202).
  • CVE-2026-42005: crafted web request can cause unlimited memory allocation in the internal web server and lead to a DoS (bsc#1269201).
Record
openSUSE-SU-2026:21533-1
Updated
2026-11-02
OSVSUSE-SU-2026:23123-1 No score

Security update for dnsdist

This update for dnsdist fixes the following issues:

Update to 1.9.15.

Changes for dnsdist:

Security issues fixed:

  • CVE-2026-40011: invalid output produced in the prometheus endpoint when a large number of crafted DNS queries are sent (bsc#1269204).
  • CVE-2026-40208: processing of DoH3 queries can be delayed via DoH3 GET queries with an invalid DATA frames (bsc#1269207).
  • CVE-2026-40209: outgoing TCP connections to backend can get stuck until a timeout occurs when specially crafted IXFR queries are sent (bsc#1269206).
  • CVE-2026-40210: out-of-bounds read when SetMacAddrAction is used can lead to uninitialized memory being sent over the network or a crash (bsc#1269205).
  • CVE-2026-40211: crafted DNS over HTTP/3 queries can trigger an exception that prevents memory from being freed and can lead to an OOM condition (bsc#1269203).
  • CVE-2026-42004: crafted EDNS OPT record will be ignored by filtering rules, but will be rewritten as a valid OPT record when EDNS Client Subnet is inserted (bsc#1269202).
  • CVE-2026-42005: crafted web request can cause unlimited memory allocation in the internal web server and lead to a DoS (bsc#1269201).
Record
SUSE-SU-2026:23123-1
Updated
2026-11-02
OSVSUSE-SU-2026:23146-1 No score

Security update for dnsdist

This update for dnsdist fixes the following issues:

Update to 1.9.15.

Changes for dnsdist:

Security issues fixed:

  • CVE-2026-40011: invalid output produced in the prometheus endpoint when a large number of crafted DNS queries are sent (bsc#1269204).
  • CVE-2026-40208: processing of DoH3 queries can be delayed via DoH3 GET queries with an invalid DATA frames (bsc#1269207).
  • CVE-2026-40209: outgoing TCP connections to backend can get stuck until a timeout occurs when specially crafted IXFR queries are sent (bsc#1269206).
  • CVE-2026-40210: out-of-bounds read when SetMacAddrAction is used can lead to uninitialized memory being sent over the network or a crash (bsc#1269205).
  • CVE-2026-40211: crafted DNS over HTTP/3 queries can trigger an exception that prevents memory from being freed and can lead to an OOM condition (bsc#1269203).
  • CVE-2026-42004: crafted EDNS OPT record will be ignored by filtering rules, but will be rewritten as a valid OPT record when EDNS Client Subnet is inserted (bsc#1269202).
  • CVE-2026-42005: crafted web request can cause unlimited memory allocation in the internal web server and lead to a DoS (bsc#1269201).
Record
SUSE-SU-2026:23146-1
Updated
2026-11-02

Affected products

Affected packages

Affected packages
PackageAffectedFixed
dnsdist
Debian:12
All versions, plus listed versions
1.7.3-21.8.0-11.8.1-11.8.2-11.8.2-2
Show 33 moreShow less
1.8.2-31.8.3-11.8.3-21.8.3-31.9.10-11.9.3-11.9.4-11.9.5-11.9.6-11.9.8-11.9.9-12.0.0-12.0.0-22.0.0-32.0.0-42.0.0-52.0.0-62.0.0~rc1-12.0.0~rc1-22.0.0~rc2-12.0.1-12.0.2-12.0.3-12.0.4-12.0.5-12.0.5-22.0.5-32.0.6-12.1.0-12.1.0-22.1.1-12.1.2-12.1.3-1
None known
dnsdist
Debian:13
before 1.9.15-0+deb13u1, plus listed versions
1.9.10-11.9.10-1+deb13u11.9.14-0+deb13u1
1.9.15-0+deb13u1
dnsdist
Debian:14
before 2.1.0-1, plus listed versions
1.9.10-12.0.0-12.0.0-22.0.0-32.0.0-4
Show 13 moreShow less
2.0.0-52.0.0-62.0.0~rc1-12.0.0~rc1-22.0.0~rc2-12.0.1-12.0.2-12.0.3-12.0.4-12.0.5-12.0.5-22.0.5-32.0.6-1
2.1.0-1
dnsdist
SUSE:Linux Enterprise Server 16.0
From an advisory covering 7 CVEs
before 1.9.15-160000.1.1
1.9.15-160000.1.1
dnsdist
SUSE:Linux Enterprise Server for SAP applications 16.0
From an advisory covering 7 CVEs
before 1.9.15-160000.1.1
1.9.15-160000.1.1
dnsdist
Ubuntu:16.04:LTS
All versions, plus listed versions
1.0.0~alpha2-1
None known
dnsdist
Ubuntu:Pro:18.04:LTS
All versions, plus listed versions
1.2.0-11.2.0-31.2.1-11.2.1-1build11.2.1-1ubuntu0.1~esm1
None known
dnsdist
Ubuntu:Pro:20.04:LTS
All versions, plus listed versions
1.4.0~rc3-11.4.0-11.4.0-1build11.4.0-1build21.4.0-1ubuntu0.1~esm1
None known
dnsdist
Ubuntu:Pro:22.04:LTS
All versions, plus listed versions
1.5.1-3build21.6.1-1build11.6.1-1ubuntu0.1~esm11.6.1-1ubuntu0.1~esm2
None known
dnsdist
Ubuntu:Pro:24.04:LTS
All versions, plus listed versions
1.8.0-11.8.2-11.8.2-21.8.2-31.8.3-1
Show 4 moreShow less
1.8.3-21.8.3-2build11.8.3-2build21.8.3-2ubuntu0.1~esm1
None known
Show 5 moreShow less
Affected packages
PackageAffectedFixed
dnsdist
Ubuntu:25.10
All versions, plus listed versions
1.9.8-11.9.10-11.9.10-1ubuntu0.1
None known
dnsdist
Ubuntu:26.10
All versions, plus listed versions
2.0.2-1build12.0.5-2ubuntu12.0.5-2ubuntu3
None known
dnsdist
Ubuntu:26.04:LTS
All versions, plus listed versions
1.9.10-12.0.1-12.0.2-12.0.2-1build1
None known
dnsdist
openSUSE:Tumbleweed
From an advisory covering 7 CVEs
before 2.0.7-1.1
2.0.7-1.1
dnsdist
openSUSE:Leap 16.0
From an advisory covering 7 CVEs
before 1.9.15-160000.1.1
1.9.15-160000.1.1

History

History
RecordedChangedSources
affected, facts
first indexedCVE List, EUVD, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-40210 is a medium vulnerability (CVSS 4.8) in Powerdns Dnsdist, published June 25, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.74%, the 54th percentile. Fixed in dnsdist 1.9.15-0+deb13u1.

References

Show 19 moreShow less
MoveEnter Open