Bug 2516403 (CVE-2026-72231)

Summary: CVE-2026-72231 kernel: batman-adv: tt: avoid request storms during pending request
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the batman-adv (Better Approach To Mobile Ad-hoc Networking) module of the Linux kernel. An incorrect check during the handling of TT (Topology Table) requests can prevent the proper cleanup of request nodes when send buffer allocation fails. This can lead to a remote attacker causing request storms, potentially resulting in a Denial of Service (DoS) condition.
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Description OSIDB Bzimport 2026-08-15 06:10:38 UTC 
In the Linux kernel, the following vulnerability has been resolved:

batman-adv: tt: avoid request storms during pending request

batadv_send_tt_request() allocates a tt_req_node when none exists for the
destination originator node. This should prevent that a multiple TT
requests are send at the same time to an originator.

But if allocation of the send buffer failed, this request must be cleaned
up again. But indicator for such a failure is "ret == false". But the
actual implementation is checking for "ret == true".

The check must be inverted to not loose the information about the TT
request directly after it was attempted to be sent out. This should avoid
potential request storms.
Comment 1 gkamathe 2026-08-18 09:05:25 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026081549-CVE-2026-72231-bfeb@gregkh/T