Is CVE-2026-5123 actively exploited?

CVE-2026-5123 has no public evidence of in-the-wild exploitation as of 2026-04-06.

What is the CVSS score for CVE-2026-5123?

CVE-2026-5123 has a CVSS score of 6.3 (MEDIUM severity). 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.

How do I patch CVE-2026-5123?

Patch guidance is available from osrg security advisories. CVEDatabase generates AI-assisted remediation guidance on demand for CVE-2026-5123.

CVE-2026-5123 - remediation guidance & executive summary

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.

CVSS Metrics

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
Attack Vector: network
Complexity: high
Privileges: none
User Action: none
Confidentiality: undefined
Integrity: undefined
Availability: undefined
Weaknesses: CWE-189 CWE-193

Metadata

Primary Vendor: OSRG
Published: 3/30/2026
Last Modified: 4/6/2026
Source: NIST NVD
Note: Verify all details with official vendor sources before applying patches.

CVE-2026-5123

Description

CVSS Metrics

Metadata

Affected Products

Remediation Guidance

Executive Summary