CVE-2023-28450: An issue was discovered in Dnsmasq before 2.90

Q: How do I fix CVE-2023-28450?

dnsmasq: upgrade to 2.90. Exact commands for each OS are on this page.

Q: Is CVE-2023-28450 being exploited?

CVE-2023-28450 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2023-28450 affect?

CVE-2023-28450 affects dnsmasq. Severity is high (CVSS 7.5). An issue was discovered in Dnsmasq before 2.90. The default maximum EDNS.0 UDP packet size was set to 4096 but should be 1232 because of DNS Flag Day 2020.

Q: How urgent is CVE-2023-28450?

Priority 51/100. High severity; Remotely exploitable, no login, no user action

This month

HIGH 7.5REMOTEUPGRADE

CVE-2023-28450 is a high-severity flaw (CVSS 7.5) affecting dnsmasq. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

An issue was discovered in Dnsmasq before 2.90. The default maximum EDNS.0 UDP packet size was set to 4096 but should be 1232 because of DNS Flag Day 2020.

Why this priority

High severity
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	1.8% (top 21%)
CISA exploited list	No
Published	2023-03-15
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: thekelleys

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2023-03-15 21:15 UTCPublished CVE record published
2026-06-17 05:47 UTCUpdated Record last modified

thekelleys dnsmasq UPGRADE

Affected: < 2.90

Fixed in: 2.90

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy dnsmasq || rpm -q dnsmasq || dnsmasq --version

2. UPGRADE to 2.90 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade dnsmasq

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade dnsmasq

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2023-28450?

dnsmasq: upgrade to 2.90. Exact commands for each OS are on this page.

Is CVE-2023-28450 being exploited?

CVE-2023-28450 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2023-28450 affect?

CVE-2023-28450 affects dnsmasq. Severity is high (CVSS 7.5). An issue was discovered in Dnsmasq before 2.90. The default maximum EDNS.0 UDP packet size was set to 4096 but should be 1232 because of DNS Flag Day 2020.

How urgent is CVE-2023-28450?

Priority 51/100. High severity; Remotely exploitable, no login, no user action

Software pages

Dnsmasq vulnerabilities

Related CVEs

CVE-2026-12725 MEDIUM 5.9 UPGRADE MITIGATE A heap-based buffer overflow was found in dnsmasq
CVE-2026-12969 MEDIUM 5.3 MITIGATE UPGRADE An out-of-bounds read vulnerability exists in dnsmasq's find_soa() function in src/rfc1035.c
CVE-2023-49441 HIGH 7.5 DOWNGRADE dnsmasq 2.9 is vulnerable to Integer Overflow via forward_query.
CVE-2022-0934 HIGH 7.5 UPGRADE MITIGATE A single-byte, non-arbitrary write/use-after-free flaw was found in dnsmasq
CVE-2021-45957 CRITICAL 9.8 DOWNGRADE Dnsmasq 2.86 has a heap-based buffer overflow in answer_request (called from FuzzAnswerTheRequest and fuzz_rfc

References

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