netty · In versions 4.2.0.Final through 4.2.15.Final and 4.1.0.Final through 4.1.135.Final, any caller that can deliver bytes
Affects nettySource GCVE Database
Not known to be exploited · CVSS 9.8 Critical · fixed in 4.1.136 : patch netty as a priority.
Data as of 5 Nov 2026, 00:01 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 53% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.1.136
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 21 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 4 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10nettypkg:deb/ubuntu/netty?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu Pro 26.04 LTSnettypkg:deb/ubuntu/netty?arch=source&distro=esm-apps/resoluteOther threats | Affected
| Fixed in– |
Ubuntu Pro 24.04 LTSnettypkg:deb/ubuntu/netty?arch=source&distro=esm-apps/nobleOther threats | Affected
| Fixed in– |
Ubuntu Pro 22.04 LTSnettypkg:deb/ubuntu/netty?arch=source&distro=esm-apps/jammyOther threats | Affected
| Fixed in– |
Ubuntu Pro 20.04 LTSnettypkg:deb/ubuntu/netty?arch=source&distro=esm-apps/focalOther threats | Affected
| Fixed in– |
Ubuntu Pro 18.04 LTSnettypkg:deb/ubuntu/netty?arch=source&distro=esm-apps/bionicOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade affected Netty versions to 4.1.136.Final or later, or 4.2.16.Final or later, where this vulnerability is fixed. No other mitigation or temporary workaround is indicated in the available data.
Description
Netty versions 4.2.0.Final through 4.2.15.Final and 4.1.0.Final through 4.1.135.Final contain a vulnerability where an attacker able to send bytes to a channel pipeline with XmlDecoder can exploit XML external entity (XXE) risks via DOCTYPE declarations. This occurs because AsyncXMLInputFactory is instantiated without security configurations, leaving DTD and entity handling active depending on the Aalto XML async parser behavior. The issue is resolved in versions 4.1.136.Final and 4.2.16.Final.