{"id":"CVE-2026-49838","title":"GoBGP is an open source Border Gateway Protocol (BGP) implementation in the Go Programming Language","summary":"GoBGP is an open source Border Gateway Protocol (BGP) implementation in the Go Programming Language. Prior to version 4.7.0, GoBGP accepts a zero-length AS_PATH during UPDATE decoding and later panics while validating that attribute for …","severity":"medium","cvss":5.9,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-129","CWE-125"],"vendor":"osrg","product":"gobgp","affected":["gobgp < 4.7.0"],"patched":["github.com/osrg/gobgp/v4 4.7.0"],"published":"2026-09-10","updated":"2026-09-16","sourceUpdated":"2026-09-16T13:42:46.970","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-49838","references":[{"url":"https://github.com/osrg/gobgp/commit/4a319a6c25630fb3cdbda3e9ccfe56e702bdaaa0","label":"security-advisories@github.com"},{"url":"https://github.com/osrg/gobgp/security/advisories/GHSA-frrj-87jh-2772","label":"security-advisories@github.com"},{"url":"https://github.com/advisories/GHSA-frrj-87jh-2772"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-49838.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-49838"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2531686"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-49838"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-49838"}],"tags":["nvd","cve.org","ghsa","go","csaf","vex","red-hat"],"epss":0.00333,"epssPercentile":0.26814,"aliases":["GHSA-frrj-87jh-2772"],"ecosystem":"go","ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-11T16:31:55.831766Z"},"ingestedAt":"2026-07-09T23:53:27.206Z","slug":"CVE-2026-49838","body":"## Overview\n\nGoBGP is an open source Border Gateway Protocol (BGP) implementation in the Go Programming Language. Prior to version 4.7.0, GoBGP accepts a zero-length AS_PATH during UPDATE decoding and later panics while validating that attribute for a confederation eBGP peer. The vulnerable path is in the BGP UPDATE validator: a malformed UPDATE that should be rejected as a malformed AS_PATH instead reaches an unchecked `p.Value[0]` access, allowing a configured confederation eBGP peer to trigger a denial of service. Version 4.7.0 patches the issue.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-49838)\n\nAffected packages:\n\n- `github.com/osrg/gobgp/v4 <= 4.6.0`\n\nPatched in:\n\n- `github.com/osrg/gobgp/v4 4.7.0`\n\nSource: https://github.com/advisories/GHSA-frrj-87jh-2772\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat OpenShift Container Platform 4 · updated 2026-09-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-49838.json)","depth":"sunlit","depthScore":33,"depthScoreParts":{"impact":32.5,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}