CVE-2026-73508
highpriority · track · 30EPSS 0.006 · 50 %ileDEEUFRNLUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.3–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (24)
Products and version ranges known to be affected.
advisories (6)
Vendor and ecosystem advisories describing this.
- NCSC-2026-0375Kwetsbaarheden verholpen in Oracle CommunicationsNL2026-09-16csaf · ncsc_nlNL
Oracle heeft 31 kwetsbaarheden verholpen in diverse Oracle Communications-producten, waaronder Oracle Communications Unified Assurance, Oracle Communications Cloud Native Core Security Edge Protection Proxy, Oracle Communications MetaSolv Solution Module - ASR, Oracle Communications Service Catalog and Design en Oracle Communications Operations Monitor.
- WID-SEC-W-2026-2511Netty: Mehrere Schwachstellen ermöglichen Denial of ServiceDeutsch2026-07-23csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Netty ausnutzen, um einen Denial of Service Angriff durchzuführen.
- WID-SEC-W-2026-3403Oracle Communications: Mehrere SchwachstellenDeutsch2026-09-15csaf · cert_bundDE
Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in Oracle Communications ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.
- WID-SEC-W-2026-4056Atlassian Produkte (Bamboo, Bitbucket, Confluence, Crucible, Fisheye und Jira): Mehrere SchwachstellenDeutsch2026-10-20csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Atlassian Bamboo, Bitbucket, Confluence, Crucible, Fisheye und Jira ausnutzen, um Daten zu manipulieren, um seine Privilegien zu erhöhen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um einen Cross-Site Scripting Angriff durchzuführen, um Sicherheitsvorkehrungen zu umgehen und um beliebigen Programmcode auszuführen.
- GHSA-mfg7-5gfp-c4w3Netty: Memory Leak in DNS Record Decoder via Malformed Domain Names2026-07-24ghsa · osvUS
### Summary A memory leak can be caused in Netty's DNS codec by sending malicious DNS packets containing invalid domain names. Because the leak occurs incrementally per packet, sustained malicious requests will cause a gradual Denial of Service. ### Details Inside `io.netty.handler.codec.dns.AbstractDnsRecord`, the parsed domain name string is passed to `IDN.toASCII(name)`. If the domain name contains characters that violate IDNA rules, `IDN.toASCII` throws an `IllegalArgumentException`. Because this exception occurs inside the constructor before the `DnsRecord` instance can assign the buffer to its content field for later release, the ByteBuf whose reference count was incremented (or newly allocated) is never released, resulting in a direct memory leak. There are several places where variants of this leak happen: - `io.netty.handler.codec.dns.DefaultDnsRecordDecoder#decodeRecord(java.lang.String, io.netty.handler.codec.dns.DnsRecordType, int, long, io.netty.buffer.ByteBuf, int, int)` invokes `in.retainedDuplicate()` or creates a new buffer `out` when constructing `DefaultDnsRawRecord` - `io.netty.handler.codec.dns.DnsCodecUtil#decompressDomainName` allocates a new `ByteBuf` and passes it to `encodeDomainName()`. If the decompressed domain name contains a null byte (`\0`), `encodeDomainName()` throws an `IllegalArgumentException`, leaking the newly allocated buffer. ### Impact Resource Exhaustion. Any application utilizing Netty's DnsRecordDecoder (such as DnsNameResolver or custom DNS servers) is vulnerable.
- CERTFR-2026-AVI-1385Multiples vulnérabilités dans les produits VMwareFrançais2026-10-26vendor · certfrFR
also known as (3)
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sources
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references (16)
External citations — patches, advisories, analysis.
- https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003bcnnvd
- https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6cnnvd
- https://github.com/netty/netty/releases/Patchcnnvd
- https://github.com/netty/netty/releases/tag/netty-4.1.136.Finalcnnvd
- https://github.com/netty/netty/releases/tag/netty-4.2.16.Finalcnnvd
- https://github.com/netty/netty/security/advisories/GHSA-mfg7-5gfp-c4w3cnnvd
- https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003benisa_euvd
- https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6enisa_euvd
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