[NEW] [high] Netty: Multiple vulnerabilities

CSIRTS triage

What

Multiple vulnerabilities can bypass security checks, manipulate requests, circumvent certificate checks, and cause denial of service.

Who is affected

Attackers can exploit these vulnerabilities in Netty deployments.

Urgency

Remediation is high urgency due to the severity and potential for exploitation.

Action

Update to the latest version of Netty to fix these vulnerabilities.

AI-assisted analysis generated from the source advisory — verify against the original.

Details

Source

CERT-Bund (BSI) Security Advisories (DE · national-cert · site)

Severity

high

Published

2026-07-30

Exploitation

Not in CISA KEV at last sync

Language

Machine-translated to English — verify against the original

Original advisory: https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-2356

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

• Low exploitation riskCVE-2026-448910.42% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 35% of all scored CVEs.
• Low exploitation riskCVE-2026-558310.42% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 35% of all scored CVEs.
• Low exploitation riskCVE-2026-558330.42% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 35% of all scored CVEs.
• Low exploitation riskCVE-2026-558510.52% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 41% of all scored CVEs.
• Low exploitation riskCVE-2026-567450.50% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 40% of all scored CVEs.
• Low exploitation riskCVE-2026-568160.43% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 35% of all scored CVEs.
• Low exploitation riskCVE-2026-568170.32% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 24% of all scored CVEs.
• Low exploitation riskCVE-2026-568190.35% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 27% of all scored CVEs.
• Low exploitation riskCVE-2026-568200.18% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 8% of all scored CVEs.
• Low exploitation riskCVE-2026-568210.14% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 4% of all scored CVEs.

Referenced CVEs

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

• highGHSA-93wv-jw9v-4972: Netty: HTTP/2 decompression leaks ByteBuf reference count when the decompressor channel i…ghsa
• unknownCVE-2026-59898: Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.13…nvd
• mediumCVE-2026-59920: Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1…nvd
• unknownCVE-2026-59901: Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.13…nvd
• unknownCVE-2026-59900: Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.13…nvd
• unknownCVE-2026-59899: Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.13…nvd
• highCVE-2026-56822: Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.13…nvd
• highCVE-2026-56821: Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.13…nvd
• mediumCVE-2026-59921: Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.13…nvd
• mediumGHSA-gcjf-9mgh-3p7g: Netty: CRLF Injection via Multipart Filename in Netty HttpPostRequestEncoderghsa
• mediumGHSA-3g8r-4pfx-jmfh: Netty: STOMP CONNECT Frame Header Injection in Nettyghsa
• highGHSA-558v-64gr-wgg4: Netty: [Bzip2Decoder] Infinite Loop in RLE State Machine Leads to Event-Loop Thread Hangghsa

Recent advisories for Netty

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

• highGHSA-93wv-jw9v-4972: Netty: HTTP/2 decompression leaks ByteBuf reference count when the decompressor channel i…ghsa · 2026-07-31
• medium[NEW] [medium] Netty: Multiple vulnerabilitiescert-bund · 2026-07-30
• high[UPDATE] [high] Netty: Multiple vulnerabilitiescert-bund · 2026-07-30
• unknownCVE-2026-59898: Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.13…nvd · 2026-07-29
• mediumCVE-2026-59920: Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1…nvd · 2026-07-29
• mediumCVE-2026-59919: Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1…nvd · 2026-07-29

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