[UPDATE] [medium] Netty: Multiple vulnerabilities

mediumCVE-2026-33870 CVE-2026-33871

A remote, anonymous attacker can exploit multiple vulnerabilities in Netty to bypass security measures and cause a denial of service.

CSIRTS triage

vendor: Netty product: Netty Denial of service Authentication bypass

What: Multiple vulnerabilities can be exploited by a remote attacker to bypass security measures and cause denial of service.
Who is affected: Deployments of Netty are affected by these vulnerabilities.
Urgency: Remediation is medium urgency due to the potential for denial-of-service attacks.
Action: Apply the latest patches for Netty.

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

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Details

Source: CERT-Bund (BSI) Security Advisories (DE · national-cert · site)
Severity: medium
Published: 2026-07-02
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-2026-0846

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-2026-338700.64% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 46% of all scored CVEs.
Moderate exploitation riskCVE-2026-338711.1% 30-day exploitation probability. Patch within normal cadence, watch for KEV listing. Riskier than 62% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-33870	coverage & exploitation status	NVD · CVE.org
CVE-2026-33871	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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

high[NEW] [high] IBM Operational Decision Manager: Multiple vulnerabilitiescert-bund
high[UPDATE] [high] Atlassian Bamboo, Bitbucket, Confluence, Fisheye, Crucible, Jira and Jira Service Management: …cert-bund
unknownMultiple vulnerabilities in IBM products (June 26, 2026)cert-fr-avis

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.

medium[UPDATE] [medium] Netty: Multiple vulnerabilitiescert-bund · 2026-07-10
high[UPDATE] [high] Netty: Multiple vulnerabilitiescert-bund · 2026-07-10
mediumCVE-2026-49365: Generation of Error Message Containing Sensitive Information vulnerability in Apache Camel Net…nvd · 2026-07-06
highGHSA-h2qv-fj59-j46j: Netty HAProxy: Unbalanced Reference Count in Nested PP2_TYPE_SSL TLV Parsing Leads to Mem…ghsa · 2026-06-11
mediumGHSA-c2gf-v879-257j: netty-codec-http2: ByteBuf Reference-Count Leak in DelegatingDecompressorFrameListener Le…ghsa · 2026-06-11
highGHSA-6jv9-x5w9-2ccm: Netty's Lack of Lifecycle Cleanup Leads to Pooled ByteBuf Leak in RedisArrayAggregatorghsa · 2026-06-11