CVE-2026-5123: medium-severity vulnerability in osrg GoBGP
osrg GoBGP bgp.go DecodeFromBytes off-by-one
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.3epss 0.4%
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.
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
Affected products
osrg · GoBGPRelated CVEs — osrg GoBGP
In the same product, most dangerous first.
CVE-2026-7737MEDIUMosrg GoBGP BMP Parser bmp.go BMPStatisticsReport.ParseBody out-of-boundsEPSS 0.6%CVE-2025-7464MEDIUMosrg GoBGP rtr.go SplitRTR out-of-boundsEPSS 0.5%CVE-2026-7734MEDIUMosrg GoBGP SRv6 L3 Service prefix_sid.go SRv6L3ServiceAttribute.DecodeFromBytes denial of serviceEPSS 0.5%CVE-2026-7736MEDIUMosrg GoBGP mrt.go parseRibEntry integer underflowEPSS 0.5%CVE-2026-7735MEDIUMosrg GoBGP AIGP Attribute bgp.go PathAttributeAigp.DecodeFromBytes buffer overflowEPSS 0.4%CVE-2026-5124MEDIUMosrg GoBGP BGP Header bgp.go BGPHeader.DecodeFromBytes access controlEPSS 0.3%