NULL Pointer Dereference Affecting kernel-rt-debug-devel package, versions *


Severity

Recommended
0.0
medium
0
10

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
0.18% (8th percentile)

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  • Snyk IDSNYK-RHEL10-KERNELRTDEBUGDEVEL-19243470
  • published25 Aug 2026
  • disclosed22 Aug 2026

Introduced: 22 Aug 2026

NewCVE-2026-74726  (opens in a new tab)
CWE-476  (opens in a new tab)

How to fix?

There is no fixed version for RHEL:10 kernel-rt-debug-devel.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-rt-debug-devel package and not the kernel-rt-debug-devel package as distributed by RHEL. See How to fix? for RHEL:10 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

bonding: alb: re-check primary_is_promisc under RTNL in bond_alb_monitor

bond_alb_monitor() reads primary_is_promisc under RCU, then drops RCU and takes RTNL via rtnl_trylock() before undoing the promiscuity it set on the active slave. In that window the active slave can change under RTNL (RTM_DELLINK -> __bond_release_one() -> bond_alb_handle_active_change()), which already drops the promiscuity and clears primary_is_promisc. The monitor still acts on the stale decision: if the slave was removed with no failover, curr_active_slave is now NULL and the deref faults; if it failed over, the stale dev_set_promiscuity(-1) underflows the new slave's promiscuity counter and pins it in IFF_PROMISC.

Oops: general protection fault, probably for non-canonical address ... KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] Workqueue: b42 bond_alb_monitor RIP: 0010:bond_alb_monitor (drivers/net/bonding/bond_alb.c:1600) process_one_work (kernel/workqueue.c:3322) worker_thread (kernel/workqueue.c:3486) kthread (kernel/kthread.c:436) ret_from_fork (arch/x86/kernel/process.c:158) Kernel panic - not syncing: Fatal exception

Re-check primary_is_promisc (and curr_active_slave) after taking RTNL so the monitor only undoes an increment it still owns. The other bonding monitors already re-read state under RTNL in their commit phase (bond_miimon_commit/bond_ab_arp_commit); bond_alb_monitor() was the only one acting on the pre-trylock decision.

CVSS Base Scores

version 3.1