CVE-2026-55831

{"id": "CVE-2026-55831", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-55831", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-07-23T14:33:23.657664Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 3.9}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "netty", "product": "netty", "versions": [{"status": "affected", "version": ">= 4.2.0.Final, < 4.2.16.Final"}, {"status": "affected", "version": ">= 4.1.0.Final, < 4.1.136.Final"}]}]}], "published": "2026-07-21T00:17:35.383", "references": [{"url": "https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/netty/netty/releases/tag/netty-4.1.136.Final", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/netty/netty/releases/tag/netty-4.2.16.Final", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/netty/netty/security/advisories/GHSA-6jqx-86gh-f27w", "tags": ["Exploit", "Vendor Advisory"], "source": "security-advisories@github.com"}, {"url": "https://github.com/netty/netty/security/advisories/GHSA-6jqx-86gh-f27w", "tags": ["Exploit", "Vendor Advisory"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-400"}, {"lang": "en", "value": "CWE-770"}]}], "descriptions": [{"lang": "en", "value": "Netty is a network application framework for development of protocol servers and clients. Prior to 4.1.136.Final and 4.2.16.Final, Netty's SPDY SETTINGS decoder accepts a peer-declared SETTINGS entry count up to the 24-bit frame-length limit and materializes every unique setting ID in `DefaultSpdySettingsFrame`, allowing a remote SPDY/3.1 peer to send a syntactically valid roughly 2 MiB SETTINGS frame that creates 262144 map entries and amplifies network input into heap growth and ordered-map insertion work. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final."}], "lastModified": "2026-07-23T15:17:16.780", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "09BEF8E6-BE3C-4815-AAAA-2AFFCDE2D786", "versionEndExcluding": "4.1.136", "versionStartIncluding": "4.1.0"}, {"criteria": "cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4DE4BC35-4405-49B5-A2A8-A700C7F63C8B", "versionEndExcluding": "4.2.16", "versionStartIncluding": "4.2.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}