CVE-2026-73508
Netty: Memory Leak in DNS Record Decoder via Malformed Domain Names
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
Netty is an asynchronous, event-driven network application framework. Prior to 4.1.136.Final and 4.2.16.Final, io.netty.handler.codec.dns.AbstractDnsRecord, io.netty.handler.codec.dns.DefaultDnsRecordDecoder.decodeRecord(), and io.netty.handler.codec.dns.DnsCodecUtil.decompressDomainName() failed to release retained or newly allocated ByteBuf objects when IDN.toASCII() or encodeDomainName() rejected a malformed domain name, allowing unauthenticated remote DNS packets to leak direct memory incrementally until denial of service. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| NVDNVD · Analyzed | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.63% · top 50% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.3.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Mavenio.netty:netty-codec-dnsGHSA-mfg7-5gfp-c4w3 (opens in a new tab)
References (5)
- https://github.com/netty/netty/security/advisories/GHSA-mfg7-5gfp-c4w3 (opens in a new tab)x_refsource_CONFIRM
- https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b (opens in a new tab)x_refsource_MISC
- https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6 (opens in a new tab)x_refsource_MISC
- https://github.com/netty/netty/releases/tag/netty-4.1.136.Final (opens in a new tab)x_refsource_MISC
- https://github.com/netty/netty/releases/tag/netty-4.2.16.Final (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-mfg7-5gfp-c4w3 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-73508)Record last updated .