CVE-2026-129217
Received Received - Intake

Heap Buffer Overflow in FRRouting bgpd

Vulnerability report for CVE-2026-129217, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.

Publication date: 2026-11-13

Last updated on: 2026-11-13

Assigner: 57a55968-44ac-464c-a794-6ba3baad09c4

Description

In FRRouting (FRR) 8.3 through 10.5.1, bgp_notify_decapsulate_hard_reset() in bgpd/bgp_packet.c does not validate the length of the data field of a received BGP NOTIFICATION Cease/Hard Reset message (RFC 8538). When the data field is exactly one byte long, the function reads one byte past the end of a heap buffer and the 16-bit length of the encapsulated data underflows to 65535, causing a 65535-byte out-of-bounds heap read followed by an assertion failure. A remote BGP peer that has established a session and negotiated the Graceful Restart capability with the Notification (N) bit can send such a message to crash the bgpd daemon, terminating all BGP sessions (denial of service). This is fixed in 10.0.5, 10.1.5, 10.2.6, 10.3.4, 10.4.3, 10.5.2 and 10.6.0.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-11-13
Last Modified
2026-11-13
Generated
2026-11-13
AI Q&A
2026-11-13
EPSS Evaluated
N/A
NVD
EUVD

Affected Vendors & Products

Showing 9 associated CPEs

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-191 The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.
CWE-125 The product reads data past the end, or before the beginning, of the intended buffer.

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

This vulnerability exists in FRRouting (FRR) versions 8.3 through 10.5.1. It involves a function in the BGP packet handling code that fails to properly validate the length of a received BGP NOTIFICATION Cease/Hard Reset message. When the message's data field is exactly one byte long, it causes an out-of-bounds heap read and an assertion failure, crashing the bgpd daemon.

Impact Analysis

A remote BGP peer that has established a session with your system and negotiated the Graceful Restart capability can exploit this flaw. By sending a specially crafted message, they can crash the bgpd daemon, terminating all BGP sessions and causing a denial of service.

Mitigation Strategies

Upgrade FRRouting (FRR) to a fixed version: 10.0.5, 10.1.5, 10.2.6, 10.3.4, 10.4.3, 10.5.2, or 10.6.0 or later to address the vulnerability.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-129217. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart

Security Radar

News mentioning this vulnerability
Loading related security news...