Bug 2482632 (CVE-2026-46212)

Summary: CVE-2026-46212 kernel: batman-adv: bla: prevent use-after-free when deleting claims
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
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Priority: unspecified    
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` component of the Linux kernel. This vulnerability, a use-after-free, occurs during the process of deleting backbone claims. If exploited, this memory corruption issue could allow an attacker to cause a system crash, leading to a denial of service, or potentially execute unauthorized code.
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Description OSIDB Bzimport 2026-05-28 11:06:47 UTC 
In the Linux kernel, the following vulnerability has been resolved:

batman-adv: bla: prevent use-after-free when deleting claims

When batadv_bla_del_backbone_claims() removes all claims for a backbone, it
does this by dropping the link entry in the hash list. This list entry
itself was one of the references which need to be dropped at the same time
via batadv_claim_put().

But the batadv_claim_put() must not be done before the last access to the
claim object in this function. Otherwise the claim might be freed already
by the batadv_claim_release() function before the list entry was dropped.
Comment 1 Keith Grant 2026-05-28 13:13:01 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026052835-CVE-2026-46212-2bca@gregkh/T