A heap-based out-of-bounds read vulnerability in the DNSSEC validation of dnsmasq allows remote attackers to cause a denial of service via a
Noroxi assessment
Priority: Monitor (action score 21/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.83% (FIRST EPSS); higher than 57% of all records.
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: azl3 dnsmasq 2.90-1 on Azure Linux 3.0 2.92-1; azl3 dnsmasq 2.92-1 on Azure Linux 3.0 2.92-1.
Low priority for now. Upgrade to azl3 dnsmasq 2.90-1 on Azure Linux 3.0 2.92-1; azl3 dnsmasq 2.92-1 on Azure Linux 3.0 2.92-1 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
A heap-based out-of-bounds read vulnerability in the DNSSEC validation of dnsmasq allows remote attackers to cause a denial of service via a crafted DNS packet.
- Published
- May 11, 2026
- Updated
- Sep 1, 2026
- EPSS
- 0.8% · 57th percentile
- CWE
- CWE-125
Report tools
Action score
21
Monitor
Low priority for now.
- CVSS
- 21 / 40 · 5.3 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.8%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| enterprise linux | 10.2 | cpe:2.3:redhat:enterprise_linux:10.2 |
| enterprise linux | 8 | cpe:2.3:redhat:enterprise_linux:8 |
| enterprise linux | 9 | cpe:2.3:redhat:enterprise_linux:9 |
| rhel eus | 9.6 | cpe:2.3:redhat:rhel_eus:9.6 |
| openshift | 4.19 | cpe:2.3:redhat:openshift:4.19 |
| enterprise linux | 6 | cpe:2.3:redhat:enterprise_linux:6 |
| enterprise linux | 7 | cpe:2.3:redhat:enterprise_linux:7 |
Versions reported by the vendor
Affected version ranges reported by the assigning authority (certcc). Independent of NVD's CPE analysis and usually ahead of it.
dnsmasq dnsmasq
- before 2.92rel2affected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| AlmaLinux:10 | dnsmasq | before 2.90-7.el10_2 | 2.90-7.el10_2 |
| AlmaLinux:10 | dnsmasq-utils | before 2.90-7.el10_2 | 2.90-7.el10_2 |
| AlmaLinux:8 | dnsmasq | before 2.79-36.el8_10 | 2.79-36.el8_10 |
| AlmaLinux:8 | dnsmasq-utils | before 2.79-36.el8_10 | 2.79-36.el8_10 |
| AlmaLinux:9 | dnsmasq | before 2.85-18.el9_8.1 | 2.85-18.el9_8.1 |
| AlmaLinux:9 | dnsmasq-utils | before 2.85-18.el9_8.1 | 2.85-18.el9_8.1 |
| Alpine:v3.22 | dnsmasq | before 2.91-r1 | 2.91-r1 |
| Alpine:v3.24 | dnsmasq | before 2.92_p2-r0 | 2.92_p2-r0 |
| Debian:12 | dnsmasq | before 2.90-4~deb12u2 | 2.90-4~deb12u2 |
| Debian:13 | dnsmasq | before 2.91-1+deb13u1 | 2.91-1+deb13u1 |
| Debian:14 | dnsmasq | before 2.92-5 | 2.92-5 |
| openSUSE:Tumbleweed | dnsmasq | before 2.92rel2-1.1 | 2.92rel2-1.1 |
| Red Hat:enterprise_linux:10.2 | dnsmasq | before 0:2.90-7.el10_2 | 0:2.90-7.el10_2 |
| Red Hat:enterprise_linux:10.2 | dnsmasq-debuginfo | before 0:2.90-7.el10_2 | 0:2.90-7.el10_2 |
| Red Hat:enterprise_linux:10.2 | dnsmasq-debugsource | before 0:2.90-7.el10_2 | 0:2.90-7.el10_2 |
| Red Hat:enterprise_linux:10.2 | dnsmasq-utils | before 0:2.90-7.el10_2 | 0:2.90-7.el10_2 |
| Red Hat:enterprise_linux:10.2 | dnsmasq-utils-debuginfo | before 0:2.90-7.el10_2 | 0:2.90-7.el10_2 |
| Red Hat:enterprise_linux:8::appstream | dnsmasq | before 0:2.79-36.el8_10 | 0:2.79-36.el8_10 |
| Red Hat:enterprise_linux:8::appstream | dnsmasq-debuginfo | before 0:2.79-36.el8_10 | 0:2.79-36.el8_10 |
| Red Hat:enterprise_linux:8::appstream | dnsmasq-debugsource | before 0:2.79-36.el8_10 | 0:2.79-36.el8_10 |
| Red Hat:enterprise_linux:8::appstream | dnsmasq-utils | before 0:2.79-36.el8_10 | 0:2.79-36.el8_10 |
| Red Hat:enterprise_linux:8::appstream | dnsmasq-utils-debuginfo | before 0:2.79-36.el8_10 | 0:2.79-36.el8_10 |
| Red Hat:enterprise_linux:9::appstream | dnsmasq | before 0:2.85-18.el9_8.1 | 0:2.85-18.el9_8.1 |
| Red Hat:enterprise_linux:9::appstream | dnsmasq-debuginfo | before 0:2.85-18.el9_8.1 | 0:2.85-18.el9_8.1 |
+12
Same product
dnsmasq: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-4892A heap-based out-of-bounds write vulnerability in the DHCPv6 implementation of dnsmasq allows local attackers to execute arbitrary code with33Monitor
- CVE-2026-4890A Denial of Service (DoS) vulnerability in the DNSSEC validation of dnsmasq allows remote attackers to cause a denial of service via a craft30Monitor
- CVE-2026-5172A buffer overflow in dnsmasq’s extract_addresses() function allows an attacker to trigger a heap out-of-bounds read and crash by exploiting 29Monitor
Published before and after this one in the same product
- ← EarlierCVE-2006-2017Apr 25, 2006 · Dnsmasq 2.29 allows remote attackers to cause a denial of service (application crash) via a DHCP client broadcast reply request.21Monitor
- ← EarlierCVE-2026-2291May 11, 2026 · dnsmasqs extract_name() function can be abused to cause a heap buffer overflow, allowing an attacker to inject false DNS cache entries, whic29Monitor
- Later →CVE-2026-4893May 11, 2026 · An information disclosure vulnerability in dnsmasq allows remote attackers to bypass source checks via a crafted DNS packet with RFC 7871 cl21Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| azl3 dnsmasq 2.90-1 on Azure Linux 3.0 | 2.92-1 · CBL-Mariner Releases | Microsoft (MSRC) |
| azl3 dnsmasq 2.92-1 on Azure Linux 3.0 | 2.92-1 · CBL-Mariner Releases | Microsoft (MSRC) |
| almalinux:dnsmasq | 2.90-7.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:dnsmasq-utils | 2.90-7.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| alpine:dnsmasq | 2.91-r1 · Alpine:v3.22 | Package registry (OSV) |
| debian:dnsmasq | 2.90-4~deb12u2 · Debian:12 | Package registry (OSV) |
| opensuse:dnsmasq | 2.92rel2-1.1 · openSUSE:Tumbleweed | Package registry (OSV) |
| red hat:dnsmasq | 0:2.90-7.el10_2 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| red hat:dnsmasq-debuginfo | 0:2.90-7.el10_2 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| red hat:dnsmasq-debugsource | 0:2.90-7.el10_2 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| red hat:dnsmasq-utils | 0:2.90-7.el10_2 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| red hat:dnsmasq-utils-debuginfo | 0:2.90-7.el10_2 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
| rocky linux:dnsmasq | 0:2.90-7.el10_2 · Rocky Linux:10 | Package registry (OSV) |
| suse:dnsmasq | 2.92rel2-18.27.1 · SUSE:Linux Enterprise Server 12 SP5-LTSS | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-51720 days apartA buffer overflow in dnsmasq’s extract_addresses() function allows an attacker to trigger a heap out-of-bounds read and crash by exploiting 29Monitor
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- low · data can be read
- Integrity
- none
- Availability
- none
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- Low
- Integrity impact
- None
- Availability impact
- None
Weakness class (CWE)
CWE-125 · Out-of-bounds ReadCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (13 more)Show less
- github.com/NixOS/nixpkgs/pull/519093
- github.com/pi-hole/FTL/releases/tag/v6.6.2
- lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2026q2/018471.html
- thekelleys.org.uk/dnsmasq/CVE/
- www.kb.cert.org/vuls/id/471747
- access.redhat.com/errata/RHSA-2026:19158
- access.redhat.com/errata/RHSA-2026:19373
- access.redhat.com/errata/RHSA-2026:20589
- access.redhat.com/errata/RHSA-2026:34508
- access.redhat.com/errata/RHSA-2026:40762
- access.redhat.com/security/cve/CVE-2026-4891
- bugzilla.redhat.com/show_bug.cgi?id=2458517
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4891.json
Vendor advisories and official records. Exploit/PoC links are deliberately left out.