CVE-2023-3748: Inifinite loop in babld message parsing may cause dos

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-07-24 · updated 2026-06-17
Weakness: CWE-835

Description

A flaw was found in FRRouting when parsing certain babeld unicast hello messages that are intended to be ignored. This issue may allow an attacker to send specially crafted hello messages with the unicast flag set, the interval field set to 0, or any TLV that contains a sub-TLV with the Mandatory flag set to enter an infinite loop and cause a denial of service.

Affected products

FRRouting: before 8.5 — fixed in 8.5

How to fix

Upgrade to a fixed version: FRRouting 8.5. Check the vendor advisory for mitigations.

References

https://access.redhat.com/security/cve/CVE-2023-3748
https://bugzilla.redhat.com/show_bug.cgi?id=2223668
https://access.redhat.com/security/cve/CVE-2023-3748
https://bugzilla.redhat.com/show_bug.cgi?id=2223668

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