Bug 2454319 (CVE-2026-23412)

Summary: CVE-2026-23412 kernel: netfilter: bpf: defer hook memory release until rcu readers are done
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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Doc Text:
A flaw was found in the Linux kernel's netfilter BPF (Berkeley Packet Filter) component. A local attacker could exploit this by initiating a concurrent process to dump hooks via `nfnetlink_hooks`, which triggers a use-after-free vulnerability. This could lead to system instability or a denial of service (DoS) condition.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-04-02 12:02:15 UTC 
In the Linux kernel, the following vulnerability has been resolved:

netfilter: bpf: defer hook memory release until rcu readers are done

Yiming Qian reports UaF when concurrent process is dumping hooks via
nfnetlink_hooks:

BUG: KASAN: slab-use-after-free in nfnl_hook_dump_one.isra.0+0xe71/0x10f0
Read of size 8 at addr ffff888003edbf88 by task poc/79
Call Trace:
 <TASK>
 nfnl_hook_dump_one.isra.0+0xe71/0x10f0
 netlink_dump+0x554/0x12b0
 nfnl_hook_get+0x176/0x230
 [..]

Defer release until after concurrent readers have completed.
Comment 1 Jon Moroney 2026-04-02 21:28:14 UTC Comment hidden (spam)