Microsoft security update for CVE-2026-31546 — cbl2 kernel 5.15.202.1-1
🔗 CVE IDs covered (1)
📋 Microsoft's advisory
EchelonGraph does not copy Microsoft's advisory page: its FAQ and remediation text are not shown here. Read the advisory on https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-31546. This page also shows what EchelonGraph holds for CVE-2026-31546, with the description from its CVE record, which the CVE Numbering Authority that assigned the CVE wrote: for a CVE Microsoft assigned, often in the words of Microsoft's own advisory.
🎯 Affected products2
- cbl2 kernel 5.15.202.1-1 on CBL Mariner 2.0
- cbl2 kernel 5.15.202.1-1 on CBL-Mariner 2.0
✅ Updates Microsoft lists: 1 update
1 row: one per KB article or update, update type and fixed build. Their details are on Microsoft's advisory.
| KB article | Update | Fixed build |
|---|---|---|
| — | Security Update | — |
🧭 EchelonGraph on CVE-2026-31546
- EchelonGraph score
- 5.5 MEDIUM
- CISA KEV
- Not listed
- Fix status
- A fix is available — apply it.
Description from the CVE record (CVE.org), as published by its numbering authority
In the Linux kernel, the following vulnerability has been resolved: net: bonding: fix NULL deref in bond_debug_rlb_hash_show rlb_clear_slave intentionally keeps RLB hash-table entries on the rx_hashtbl_used_head list with slave set to NULL when no replacement slave is available. However, bond_debug_rlb_hash_show visites client_info->slave without checking if it's NULL. Other used-list iterators in bond_alb.c already handle this NULL-slave state safely: - rlb_update_client returns early on !client_info->slave - rlb_req_update_slave_clients, rlb_clear_slave, and rlb_rebalance compare slave values before visiting - lb_req_update_subnet_clients continues if slave is NULL The following NULL deref crash can be trigger in bond_debug_rlb_hash_show: [ 1.289791] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 1.292058] RIP: 0010:bond_debug_rlb_hash_show (drivers/net/bonding/bond_debugfs.c:41) [ 1.293101] RSP: 0018:ffffc900004a7d00 EFLAGS: 00010286 [ 1.293333] RAX: 0000000000000000 RBX: ffff888102b48200 RCX: ffff888102b48204 [ 1.293631] RDX: ffff888102b48200 RSI: ffffffff839daad5 RDI: ffff888102815078 [ 1.293924] RBP: ffff888102815078 R08: ffff888102b4820e R09: 0000000000000000 [ 1.294267] R10: 0000000000000000 R11: 0000000000000000 R12: ffff888100f929c0 [ 1.294564] R13: ffff888100f92a00 R14: 0000000000000001 R15: ffffc900004a7ed8 [ 1.294864] FS: 0000000001395380(0000) GS:ffff888196e75000(0000) knlGS:0000000000000000 [ 1.295239] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.295480] CR2: 0000000000000000 CR3: 0000000102adc004 CR4: 0000000000772ef0 [ 1.295897] Call Trace: [ 1.296134] seq_read_iter (fs/seq_file.c:231) [ 1.296341] seq_read (fs/seq_file.c:164) [ 1.296493] full_proxy_read (fs/debugfs/file.c:378 (discriminator 1)) [ 1.296658] vfs_read (fs/read_write.c:572) [ 1.296981] ksys_read (fs/read_write.c:717) [ 1.297132] do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1)) [ 1.297325] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) Add a NULL check and print "(none)" for entries with no assigned slave.
Published by kernel.org, the CVE Numbering Authority that assigned CVE-2026-31546, in its CVE record at CVE.org; reused under the CVE Program's Terms of Use (its licence and MITRE's copyright notice are in our Terms of Service).