{"api_version":"1","generated_at":"2026-09-12T10:29:28+00:00","cve":"CVE-2026-49837","urls":{"html":"https://cve.report/CVE-2026-49837","api":"https://cve.report/api/cve/CVE-2026-49837.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-49837","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-49837"},"summary":{"title":"GoBGP: BGP OPEN capability parser may read capability values outside declared CapLen boundaries","description":"GoBGP is an open source Border Gateway Protocol (BGP) implementation in the Go Programming Language. Versions prior to 4.6.0 contain a BGP OPEN capability parsing issue where several concrete capability decoders may parse data from the full remaining capability buffer instead of the slice bounded by the declared capability length, `CapLen`. A malformed BGP OPEN message can cause bytes from a following capability to be interpreted as part of the current capability. The most security-relevant case is the 4-octet AS capability, where a capability with `CapLen == 0` may cause the parser to read bytes from the following capability as the 4-octet AS value. This parsed value may later affect peer AS validation during BGP session establishment. 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Versions prior to 4.6.0 contain a BGP OPEN capability parsing issue where several concrete capability decoders may parse data from the full remaining capability buffer instead of the slice bounded by the declared capability length, `CapLen`. A malformed BGP OPEN message can cause bytes from a following capability to be interpreted as part of the current capability. The most security-relevant case is the 4-octet AS capability, where a capability with `CapLen == 0` may cause the parser to read bytes from the following capability as the 4-octet AS value. This parsed value may later affect peer AS validation during BGP session establishment. Version 4.6.0 patches the issue.","Type":"Description","Title":"GoBGP: BGP OPEN capability parser may read capability values out"}]}}}