{"id":"CVE-2026-5123","aliases":["DEBIAN-CVE-2026-5123","EUVD-2026-17109","GHSA-m763-9mqf-95rq","UBUNTU-CVE-2026-5123"],"status":"published","title":"osrg GoBGP bgp.go DecodeFromBytes off-by-one","description":"A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.","severity":{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00425,"percentile":0.37075,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-189","CWE-193"],"published":"2026-03-30T15:15:14Z","modified":"2026-10-28T02:30:31Z","fixes":[{"ecosystem":"Debian:14","package":"gobgp","fixed_in":["4.4.0-1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:12","package":"gobgp","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.10.0-1","3.16.0-1","3.19.0-1","3.21.0-1","3.23.0-1","3.25.0-1","3.27.0-1","3.28.0-1","3.29.0-1","3.30.0-1","3.31.0-1","3.32.0-1","3.33.0-1","3.35.0-1","3.36.0-1","3.36.0-2","4.3.0-1","4.4.0-1","4.5.0-1","4.5.0-1~bpo13+1","4.6.0-1","4.6.0-2","4.6.0-2~bpo13+1","4.7.0-1","4.7.0-1~bpo13+1","4.8.0-1","4.8.0-2~exp1"]},{"source":"osv","ecosystem":"Debian:13","package":"gobgp","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.36.0-2","4.3.0-1","4.4.0-1","4.5.0-1","4.5.0-1~bpo13+1","4.6.0-1","4.6.0-2","4.6.0-2~bpo13+1","4.7.0-1","4.7.0-1~bpo13+1","4.8.0-1","4.8.0-2~exp1"]},{"source":"osv","ecosystem":"Debian:14","package":"gobgp","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.4.0-1"}]}],"versions":["3.36.0-2","4.3.0-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"gobgp","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.15-1","1.29-1","1.29-1ubuntu0.1+esm1","1.29-1ubuntu0.1+esm2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"gobgp","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.33-1","2.11.0-1","2.12.0-1","2.12.0-1ubuntu0.1~esm1","2.12.0-1ubuntu0.1~esm2","2.12.0-1ubuntu0.1~esm3"]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"gobgp","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.25.0-2","2.25.0-3","2.25.0-3build1","2.25.0-3ubuntu0.1","2.25.0-3ubuntu0.1+esm1","2.25.0-3ubuntu0.1+esm2","2.25.0-3ubuntu0.1+esm3","2.25.0-3ubuntu0.1+esm4"]},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"gobgp","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.16.0-1build1","3.19.0-1","3.21.0-1","3.23.0-1","3.23.0-1ubuntu0.1","3.23.0-1ubuntu0.2","3.23.0-1ubuntu0.2+esm1","3.23.0-1ubuntu0.3","3.23.0-1ubuntu0.3+esm1","3.23.0-1ubuntu0.3+esm2","3.23.0-1ubuntu0.3+esm3","3.23.0-1ubuntu0.3+esm4"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"gobgp","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.35.0-1","3.36.0-2"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"gobgp","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.36.0-2build1","4.8.0-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:26.04:LTS","package":"gobgp","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.36.0-2","3.36.0-2build1","3.36.0-2ubuntu0.1~esm1"]}],"products":[{"vendor":"osrg","product":"gobgp"}],"references":[{"url":"https://vuldb.com/vuln/354155","tags":["vdb-entry","technical-description","Third Party Advisory","VDB Entry","advisory"]},{"url":"https://vuldb.com/vuln/354155/cti","tags":["signature","permissions-required","Permissions Required","VDB Entry","report"]},{"url":"https://vuldb.com/submit/780179","tags":["third-party-advisory","Third Party Advisory","VDB Entry","advisory"]},{"url":"https://github.com/osrg/gobgp/pull/3342","tags":["issue-tracking","patch","Issue Tracking","fix","report"]},{"url":"https://github.com/osrg/gobgp/commit/67c059413470df64bc20801c46f64058e88f800f","tags":["patch","Patch","fix"]},{"url":"https://github.com/osrg/gobgp/","tags":["product","Product","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-5123","tags":["advisory"]},{"url":"https://github.com/osrg/gobgp"},{"url":"https://github.com/advisories/GHSA-m763-9mqf-95rq"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/5xxx/CVE-2026-5123.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-5123","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-5123","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-5123","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-5123","title":"osrg GoBGP bgp.go DecodeFromBytes off-by-one","description":"A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.","status":"published","published":"2026-03-30T15:15:14.229Z","modified":"2026-04-01T18:10:27.344Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X","level":"medium","assessor":"cna"},{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L/E:X/RL:O/RC:C","level":"low","assessor":"cna"},{"version":"3.0","score":3.7,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L/E:X/RL:O/RC:C","level":"low","assessor":"cna"},{"version":"2.0","score":2.6,"vector":"AV:N/AC:H/Au:N/C:N/I:N/A:P/E:ND/RL:OF/RC:C","assessor":"cna"}],"cwes":["CWE-193","CWE-189"],"updated_at":"2026-11-02T13:39:27.849196Z"}],"euvd":[{"id":"EUVD-2026-17109","description":"A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.","status":"published","published":"2026-03-30T15:15:14Z","modified":"2026-04-01T18:10:27Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X","level":"medium"}],"updated_at":"2026-11-02T19:25:24.09733Z"}],"ghsa":[{"id":"GHSA-m763-9mqf-95rq","title":"A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function...","description":"A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.","status":"published","published":"2026-03-30T18:31:17Z","modified":"2026-03-30T18:31:25Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"},{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low"}],"updated_at":"2026-11-02T15:06:55.849021Z"}],"nvd":[{"id":"CVE-2026-5123","description":"A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.","status":"published","published":"2026-03-30T16:16:10.123Z","modified":"2026-06-17T10:58:28.503Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"},{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low","assessor":"secondary"},{"version":"2.0","score":2.6,"vector":"AV:N/AC:H/Au:N/C:N/I:N/A:P","level":"low","assessor":"secondary"}],"cwes":["CWE-189","CWE-193"],"updated_at":"2026-11-02T14:12:12.261218Z"}],"osv":[{"id":"CVE-2026-5123","title":"osrg GoBGP bgp.go DecodeFromBytes off-by-one","description":"A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.","status":"published","published":"2026-03-30T15:15:14.229Z","modified":"2026-10-28T02:30:31.566236635Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X","level":"medium"}],"cwes":["CWE-189","CWE-193"],"updated_at":"2026-11-02T15:45:07.431113Z"},{"id":"DEBIAN-CVE-2026-5123","description":"A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.","status":"published","published":"2026-03-30T16:16:10.123Z","modified":"2026-10-01T03:03:24.761882687Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"}],"updated_at":"2026-11-02T15:45:56.877408Z"},{"id":"UBUNTU-CVE-2026-5123","description":"A weakness has been identified in osrg GoBGP up to 4.3.0. This impacts the function DecodeFromBytes of the file pkg/packet/bgp/bgp.go. Executing a manipulation of the argument data[1] can lead to off-by-one. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is said to be difficult. This patch is called 67c059413470df64bc20801c46f64058e88f800f. A patch should be applied to remediate this issue.","status":"published","published":"2026-03-30T16:16:00Z","modified":"2026-10-17T12:58:33.704884052Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low"},{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T16:56:33.391918Z"}]}}