CVE-2026-73507
highpriority · track · 0EPSS 0.008 · 56 %ileDEEUFRUSEPSS · 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.xml.XmlFrameDecoder.decode() failed to preserve closing-tag parser state across invocations, so an unauthenticated remote attacker could trickle-feed repeated </ sequences that repeatedly rescanned the accumulated buffer and exhausted an EventLoop thread's CPU, causing denial of service with a maxFrameLength of 1 MB. 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 · 6.9–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (18)
Products and version ranges known to be affected.
advisories (5)
Vendor and ecosystem advisories describing this.
- 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-2026-3376Atlassian Bamboo, Bitbucket, Confluence, Fisheye/Crucible, Jira Software und Jira Service Management: Mehrere SchwachstellenDeutsch2026-09-15csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Atlassian Bamboo, Bitbucket, Confluence, Fisheye/Crucible, Jira Software und Jira Service Management ausnutzen, um beliebigen Programmcode auszuführen, Sicherheitsmaßnahmen zu umgehen, serverseitige Request-Forgery-Angriffe (SSRF) durchzuführen, Cross-Site-Scripting-Angriffe zu starten, sensible Informationen offenzulegen, Daten zu manipulieren oder Denial-of-Service-Zustände herbeizuführen.
- 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-v74w-7mr3-4qg3Netty: Denial of Service in XmlFrameDecoder via CPU Exhaustion2026-07-24ghsa · osvUS
### Summary An attacker can cause Denial of Service by sending a specially crafted malicious XML payload (e.g., repeated `</` characters) to a Netty server utilizing XmlFrameDecoder, causing the server's EventLoop thread to exhaust CPU resources and become unresponsive. ### Details `io.netty.handler.codec.xml.XmlFrameDecoder` suffers from a vulnerability resulting in CPU exhaustion. When `<` followed by `/` is encountered, the decoder scans the remaining buffer for a closing `>`. Because the parser state is not saved between `decode()` invocations, an attacker can trickle-feed a payload of `</` characters. This forces the decoder to repeatedly rescan the entire accumulated buffer. A 1MB `maxFrameLength` is enough to completely hang a server's thread while it loops endlessly. ### Impact Denial of Service via CPU Exhaustion. Any application utilizing Netty's XmlFrameDecoder is impacted. An unauthenticated remote attacker can exploit this flaw by sending a modest amount of malformed XML data to an exposed port.
- CERTFR-2026-AVI-1385Multiples vulnérabilités dans les produits VMwareFrançais2026-10-26vendor · certfrFR
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
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-v74w-7mr3-4qg3cnnvd
- https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003benisa_euvd
- https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6enisa_euvd
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