Bug 2516857 (CVE-2026-74281)

Summary: CVE-2026-74281 kernel: tipc: reject inverted service ranges from peer bindings
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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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 Transparent Inter-Process Communication (TIPC) module. A remote attacker, acting as a peer node, could exploit this by sending specially crafted PUBLICATION messages with inverted service ranges. This oversight in validating service range bounds allows the attacker to cause unbounded memory leaks in the binding table, leading to a denial of service (DoS) for the affected system.
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Description OSIDB Bzimport 2026-08-15 06:37:07 UTC 
In the Linux kernel, the following vulnerability has been resolved:

tipc: reject inverted service ranges from peer bindings

tipc_update_nametbl() inserts a binding advertised by a peer node using
the lower and upper service-range bounds taken directly from the wire,
without checking that lower <= upper. The local bind path validates the
ordering (tipc_uaddr_valid()), but the name-distribution path does not.

A binding with lower > upper is inserted at the far end of the
service-range rbtree (keyed on lower) where no lookup or withdrawal can
ever match it (service_range_foreach_match() requires sr->lower <= end).
The publication, its service_range node and the augmented rbtree entry
are then leaked for the lifetime of the namespace, and there is no
per-peer cap equivalent to TIPC_MAX_PUBL on locally created bindings.

Reject inverted ranges in the network path as well. A peer node can
otherwise leak unbounded binding-table memory by sending PUBLICATION
items with lower > upper.
Comment 1 gkamathe 2026-08-19 12:38:38 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026081546-CVE-2026-74281-fc97@gregkh/T