CVE-2026-89486

High

Description

In the Linux kernel, the following vulnerability has been resolved: ipmi: Fix use-after-free of cmd_rcvr in _ipmi_destroy_user() Commit 9e91f8a6c868 ("ipmi:msghandler: Remove srcu for the ipmi_interfaces list") dropped the synchronize_rcu() between unlinking the command receivers from intf->cmd_rcvrs and freeing them, updating only the comment that explains why the barrier is needed. The cmd_rcvrs list is still traversed under plain RCU: find_cmd_rcvr() walks it inside rcu_read_lock(), and handle_ipmb_get_msg_cmd() borrows rcvr->user from that lookup within the same read-side section. Without the grace period, _ipmi_destroy_user() can kfree() a cmd_rcvr while a reader still holds a pointer to it, causing a use-after-free. The rework only made srcu unnecessary for the interfaces list; the cmd_rcvrs list still relies on plain RCU. Restore the synchronize_rcu() before freeing the receivers.

SeverityHigh
CVSS7.8
Exploit probability—
ProductLinux
PublishedSep 11, 2026
First seenSep 11, 2026

How to fix

Update
  • Linux Linux3088e41292fecf132f85f79af5ee4d620b9ff1b4, 5dc0b2a9af95a97861c1bffaf1687a3173e395c5, 05ec76cfbce653e07cec19b9b8b20e33449d5d87 or later

Affected products

ProductAffected versionsFixed in
Linux Linux9e91f8a6c8688e27f4ccce7db457da87d6458836 ≤ v < 3088e41292fecf132f85f79af5ee4d620b9ff1b4, 9e91f8a6c8688e27f4ccce7db457da87d6458836 ≤ v < 5dc0b2a9af95a97861c1bffaf1687a3173e395c5, 9e91f8a6c8688e27f4ccce7db457da87d6458836 ≤ v < 05ec76cfbce653e07cec19b9b8b20e33449d5d87, 6.163088e41292fecf132f85f79af5ee4d620b9ff1b4, 5dc0b2a9af95a97861c1bffaf1687a3173e395c5, 05ec76cfbce653e07cec19b9b8b20e33449d5d87

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.

CVE-2026-89486 · Linux · Dark Radar