Bug 2516494 (CVE-2026-72226)

Summary: CVE-2026-72226 kernel: batman-adv: tt: prevent TVLV OOB check overflow
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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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 Linux kernel's batman-adv (Better Approach To Mobile Ad-hoc Networking - Advanced) module. An integer overflow can occur when calculating the length of a Translation Table Type-Length-Value (TVLV) unicast message. This overflow can lead to invalid safety checks, allowing an out-of-bounds write to the TVLV buffer. This vulnerability could result in memory corruption.
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Description OSIDB Bzimport 2026-08-15 06:15:28 UTC 
In the Linux kernel, the following vulnerability has been resolved:

batman-adv: tt: prevent TVLV OOB check overflow

A TT unicast TVLV contains the number of VLANs stored in it. This number is
an u16 and gets multiplied by the size of the struct
batadv_tvlv_tt_vlan_data (8 bytes). The size can therefore overflow the u16
used to store the tt_vlan_len. All additional safety checks to prevent
out-of-bounds access of the TVLV buffer are invalid due to this overflow.

Using size_t prevents this overflow and ensures that the safety checks
compare against the actual buffer requirements.
Comment 1 Keith Grant 2026-08-18 16:33:38 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026081548-CVE-2026-72226-87e0@gregkh/T