VulnerabilityReceived

CVE-2026-49838

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.

MEDIUM 5.9EPSS 0.33%

Does this matter?

Lower severity and a low EPSS score (0.33%). Track it; it rarely justifies an emergency change on its own.

Description

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 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.

CVSS 3.1: 5.9 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.33% probability · 26th percentile
CISA KEV: Not listed
Weakness: CWE-129
Source: security-advisories@github.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.