What is CVE-2025-43972?

CVE-2025-43972 is a medium-severity vulnerability in Gobgp, classified under Improper Validation of Specified Quantity in Input. CVSS score: 6.8/10. Published 2025-04-21.

How severe is CVE-2025-43972?

Medium severity. CVSS v3 base score is 6.8 out of 10.

Vulnerability in Gobgp

CVE-2025-43972

An issue was discovered in GoBGP before 3.35.0. An attacker can cause a crash in the pkg/packet/bgp/bgp.go flowspec parser by sending fewer than 20 bytes in a certain context.

Published 2025-04-21 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.006 (46.3th percentile), scored 2026-10-26.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 46.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.006 · change: +0.000

Affected products

Gobgp — versions 0
Osrg Gobgp

Weakness classification (CWE)

CWE-1284 — Improper Validation of Specified Quantity in Input

References

github.com/osrg/gobgp/compare/v3.34.0...v3.35.0 (Patch, Release Notes)
github.com/osrg/gobgp/commit/ca7383f450f7b296c5389feceef2467de5ab6e5a (Patch)

Frequently asked questions

What is CVE-2025-43972?: CVE-2025-43972 is a medium-severity vulnerability in Gobgp, classified under Improper Validation of Specified Quantity in Input. CVSS score: 6.8/10. Published 2025-04-21.
How severe is CVE-2025-43972?: Medium severity. CVSS v3 base score is 6.8 out of 10.