CVE-2026-37459
frr: denial of service via crafted BGP UPDATE message
Severity
ImportantRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · May 4, 2026
Updated · June 28, 2026
Description
A flaw was found in FRRouting (FRR). An unauthenticated remote attacker can exploit an integer underflow vulnerability by supplying a specially crafted BGP (Border Gateway Protocol) UPDATE message. This issue can lead to a Denial of Service (DoS).
Statement
This vulnerability allows an unauthenticated remote attacker to cause a denial of service via a specially crafted BGP UPDATE message. Due to this reason, this issue has been rated with an important severity.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update the affected package as soon as possible.
CVSS / CWE
CVSS 3.1 · 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-191 · Integer Underflow (Wrap or Wraparound)