Netty: several flaws let attackers bypass checks and crash services
Netty is a networking library used by many Java applications. Attackers could get around security checks, tamper with requests, or overload services so they stop working.
| Severity | HighVulnerability |
|---|---|
| Being exploited? | UnclearNo reports either way yet |
| Fix available? | UnclearNo fixed version published in the sources yet |
| How sure is this? | Official sourceBacked by an official source |
What happened
Multiple vulnerabilities in the Netty Java networking framework allow security bypass, request or header manipulation, certificate validation bypass, information disclosure and denial of service.
Are you affected?
You are affected if you run Java applications or services that use the Netty networking library in a vulnerable version.
Netty (affected versions not specified in the provided material)
What to do
- Identify which of your applications or services use Netty, including indirectly through other frameworks
- Check the BSI/CERT-Bund advisory and the Netty project for the fixed version and update to it
- Monitor for abnormal request behavior and service outages until patched
Timeline
- 26 Oct 2026, 12:31 UTCPublicly disclosed
- 26 Oct 2026, 12:31 UTCReported by CERT-Bund (BSI) · CERT-Bund (BSI)
- 26 Oct 2026, 12:31 UTCReported by CERT-Bund (BSI) · CERT-Bund (BSI)
- 26 Oct 2026, 12:39 UTCPicked up by Zero Radar
- 28 Oct 2026, 22:08 UTCSeverity raised to high
- 29 Oct 2026, 12:56 UTCReported by CERT-Bund (BSI) · CERT-Bund (BSI)
Sources 3 reports, oldest first
Official vendor, government CERT or advisory database
- [UPDATE] [hoch] Netty: Mehrere SchwachstellenCERT-Bund (BSI) · 26 Oct 2026, 12:31 UTC
- [UPDATE] [mittel] Netty: Mehrere SchwachstellenCERT-Bund (BSI) · 26 Oct 2026, 12:31 UTC
- [UPDATE] [mittel] Netty: Mehrere SchwachstellenCERT-Bund (BSI) · 29 Oct 2026, 12:56 UTC
Technical details
- ID
- ZR-bc01d2fd · ZR-c60c00bd · ZR-a28f3252
- Disclosed
- 26 Oct 2026, 12:31 UTC
- On Zero Radar
- 26 Oct 2026, 12:39 UTC (9 min after disclosure)
- Last change
- 29 Oct 2026, 13:05 UTC
The plain-language parts and the attack diagram were written by an AI model (anthropic/claude-haiku-5.5) from the sources above. Facts like versions, exploitation and dates come from the sources themselves. How Zero Radar works