CVE-2026-40210
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.
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
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 Medium
CVSS: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 Medium
CVSS: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 Medium
CVSS: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 Medium
CVSS: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 Medium
CVSS: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 Medium
CVSS: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 Medium
CVSS: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:
- https://www.dnsdist.org/changelog.html#change-1.9.15
- https://www.dnsdist.org/changelog.html#change-1.9.14
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
SetMacAddrActionis 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:
- https://www.dnsdist.org/changelog.html#change-1.9.15
- https://www.dnsdist.org/changelog.html#change-1.9.14
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
SetMacAddrActionis 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:
- https://www.dnsdist.org/changelog.html#change-1.9.15
- https://www.dnsdist.org/changelog.html#change-1.9.14
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
SetMacAddrActionis 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
| Package | Affected | Fixed |
|---|---|---|
dnsdistDebian: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 less1.8.2-31.8.3-11.8.3-21.8.3-31.9.10-11.9.3-11.9.4-11.9.5-11.9.6-11.9.8-11.9.9-12.0.0-12.0.0-22.0.0-32.0.0-42.0.0-52.0.0-62.0.0~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 |
dnsdistDebian: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 |
dnsdistDebian: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 less2.0.0-52.0.0-62.0.0~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 |
dnsdistSUSE:Linux Enterprise Server 16.0 From an advisory covering 7 CVEs |
before 1.9.15-160000.1.1 | 1.9.15-160000.1.1 |
dnsdistSUSE: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 |
dnsdistUbuntu:16.04:LTS |
All versions, plus listed versions 1.0.0~alpha2-1 |
None known |
dnsdistUbuntu: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 |
dnsdistUbuntu: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 |
dnsdistUbuntu: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 |
dnsdistUbuntu: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 less1.8.3-21.8.3-2build11.8.3-2build21.8.3-2ubuntu0.1~esm1 |
None known |
Show 5 moreShow less
| Package | Affected | Fixed |
|---|---|---|
dnsdistUbuntu:25.10 |
All versions, plus listed versions 1.9.8-11.9.10-11.9.10-1ubuntu0.1 |
None known |
dnsdistUbuntu:26.10 |
All versions, plus listed versions 2.0.2-1build12.0.5-2ubuntu12.0.5-2ubuntu3 |
None known |
dnsdistUbuntu:26.04:LTS |
All versions, plus listed versions 1.9.10-12.0.1-12.0.2-12.0.2-1build1 |
None known |
dnsdistopenSUSE:Tumbleweed From an advisory covering 7 CVEs |
before 2.0.7-1.1 | 2.0.7-1.1 |
dnsdistopenSUSE:Leap 16.0 From an advisory covering 7 CVEs |
before 1.9.15-160000.1.1 | 1.9.15-160000.1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| first indexed | CVE 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
dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-09.html
nvd.nist.gov/vuln/detail/CVE-2026-40210
github.com/advisories/GHSA-5292-qc6p-vf38
repo.powerdns.com
github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40210.json
github.com/PowerDNS/pdns
Show 19 moreShow less
security-tracker.debian.org/tracker/CVE-2026-40210
suse.com/support/update/announcement/2026/suse-su-202623123-1
bugzilla.suse.com/1269201
bugzilla.suse.com/1269202
bugzilla.suse.com/1269203
bugzilla.suse.com/1269204
bugzilla.suse.com/1269205
bugzilla.suse.com/1269206
bugzilla.suse.com/1269207
suse.com/security/cve/CVE-2026-40011
suse.com/security/cve/CVE-2026-40208
suse.com/security/cve/CVE-2026-40209
suse.com/security/cve/CVE-2026-40210
suse.com/security/cve/CVE-2026-40211
suse.com/security/cve/CVE-2026-42004
suse.com/security/cve/CVE-2026-42005
suse.com/support/update/announcement/2026/suse-su-202623146-1
ubuntu.com/security/CVE-2026-40210
cve.org/CVERecord?id=CVE-2026-40210