Answer in brief
CVE-2025-38443 records a High severity (CVSS 7.8) vulnerability in nbd: fix uaf in nbd_genl_connect() error path. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:6.16:rc1:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:6.16:rc2:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:6.16:rc3:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:6.16:rc4:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:6.16:rc5:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=6497ef8df568afbf5f3e38825a4590ff41611a54 <cb121c47f364b51776c4db904a6a5a90ab0a7ec5 || >=6497ef8df568afbf5f3e38825a4590ff41611a54 <91fa560c73a8126868848ed6cd70607cbf8d87e2 || >=6497ef8df568afbf5f3e38825a4590ff41611a54 <d46186eb7bbd9a11c145120f2d77effa8d4d44c2 || >=6497ef8df568afbf5f3e38825a4590ff41611a54 <8586552df591e0a367eff44af0c586213eeecc3f || >=6497ef8df568afbf5f3e38825a4590ff41611a54 <002aca89753f666d878ca0eb8584c372684ac4ba || >=6497ef8df568afbf5f3e38825a4590ff41611a54 <aa9552438ebf015fc5f9f890dbfe39f0c53cf37e | cb121c47f364b51776c4db904a6a5a90ab0a7ec5, 91fa560c73a8126868848ed6cd70607cbf8d87e2, d46186eb7bbd9a11c145120f2d77effa8d4d44c2, 8586552df591e0a367eff44af0c586213eeecc3f, 002aca89753f666d878ca0eb8584c372684ac4ba, aa9552438ebf015fc5f9f890dbfe39f0c53cf37e |
| Linux/Linuxgeneric | 5.14 | Not reported |
Published upstream
Jul 25, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 5, 2026
In the Linux kernel, the following vulnerability has been resolved: nbd: fix uaf in nbd_genl_connect() error path There is a use-after-free issue in nbd: block nbd6: Receive control failed (result -104) block nbd6: shutting down sockets ================================================================== BUG: KASAN: slab-use-after-free in recv_work+0x694/0xa80 drivers/block/nbd.c:1022 Write of size 4 at addr ffff8880295de478 by task kworker/u33:0/67 CPU: 2 UID: 0 PID: 67 Comm: kworker/u33:0 Not tainted 6.15.0-rc5-syzkaller-00123-g2c89c1b655c0 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: nbd6-recv recv_work Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xc3/0x670 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_dec include/linux/atomic/atomic-instrumented.h:592 [inline] recv_work+0x694/0xa80 drivers/block/nbd.c:1022 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> nbd_genl_connect() does not properly stop the device on certain error paths after nbd_start_device() has been called. This causes the error path to put nbd->config while recv_work continue to use the config after putting it, leading to use-after-free in recv_work. This patch moves nbd_start_device() after the backend file creation.
Quoted source text, attributed separately from HOL analysis.