CVE-2025-39813

MEDIUM EPSS 1.6%

Published Sep 16, 20259mo ago · Modified Jun 17, 20262w ago

4.7 CVSS 3.1

Medium

Published Sep 16, 2025 9mo ago

Last Modified Jun 17, 2026 2w ago

Description

In the Linux kernel, the following vulnerability has been resolved: ftrace: Fix potential warning in trace_printk_seq during ftrace_dump When calling ftrace_dump_one() concurrently with reading trace_pipe, a WARN_ON_ONCE() in trace_printk_seq() can be triggered due to a race condition. The issue occurs because: CPU0 (ftrace_dump) CPU1 (reader) echo z > /proc/sysrq-trigger !trace_empty(&iter) trace_iterator_reset(&iter) <- len = size = 0 cat /sys/kernel/tracing/trace_pipe trace_find_next_entry_inc(&iter) __find_next_entry ring_buffer_empty_cpu <- all empty return NULL trace_printk_seq(&iter.seq) WARN_ON_ONCE(s->seq.len >= s->seq.size) In the context between trace_empty() and trace_find_next_entry_inc() during ftrace_dump, the ring buffer data was consumed by other readers. This caused trace_find_next_entry_inc to return NULL, failing to populate `iter.seq`. At this point, due to the prior trace_iterator_reset, both `iter.seq.len` and `iter.seq.size` were set to 0. Since they are equal, the WARN_ON_ONCE condition is triggered. Move the trace_printk_seq() into the if block that checks to make sure the return value of trace_find_next_entry_inc() is non-NULL in ftrace_dump_one(), ensuring the 'iter.seq' is properly populated before subsequent operations.

CVSS Details

Base Score

4.7

Exploitability

1.0

Impact

3.6

Vector string

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack Vector Local

Attack Complexity High

Privileges Required Low

User Interaction None

Scope Unchanged

Confidentiality None

Integrity None

Availability High

Threat Intelligence

EPSS Exploit Probability

1.6% percentile

Exploit & Patch Status

No Known Exploit

Patch Available

Weaknesses 1

CWE-362

Affected Products 10

Vendor	Product	Version	Range
linux	linux_kernel	*	≥2.6.28 – <5.4.298
linux	linux_kernel	*	≥5.5 – <5.10.242
linux	linux_kernel	*	≥5.11 – <5.15.191
linux	linux_kernel	*	≥5.16 – <6.1.150
linux	linux_kernel	*	≥6.2 – <6.6.104
linux	linux_kernel	*	≥6.7 – <6.12.45
linux	linux_kernel	*	≥6.13 – <6.16.5
linux	linux_kernel	6.17	any
linux	linux_kernel	6.17	any
debian	debian_linux	11.0	any

References 11

cert-portal.siemens.com https://cert-portal.siemens.com/productcert/html/ssa-032379.html
git.kernel.org https://git.kernel.org/stable/c/28c8fb7ae2ad27d81c8de3c4fe608c509f6a18aa

Patch
git.kernel.org https://git.kernel.org/stable/c/4013aef2ced9b756a410f50d12df9ebe6a883e4a

Patch
git.kernel.org https://git.kernel.org/stable/c/5ab0ec206deb99eb3baf8f1d7602aeaa91dbcc85

Patch
git.kernel.org https://git.kernel.org/stable/c/a6f0f8873cc30fd4543b09adf03f7f51d293f0e6

Patch
git.kernel.org https://git.kernel.org/stable/c/ced94e137e6cd5e79c65564841d3b7695d0f5fa3

Patch
git.kernel.org https://git.kernel.org/stable/c/e80ff23ba8bdb0f41a1afe2657078e4097d13a9a

Patch
git.kernel.org https://git.kernel.org/stable/c/f299353e7ccbcc5c2ed8993c48fbe7609cbe729a

Patch
git.kernel.org https://git.kernel.org/stable/c/fbd4cf7ee4db65ef36796769fe978e9eba6f0de4

Patch
lists.debian.org https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html

Third Party Advisory
lists.debian.org https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html

Third Party Advisory

Remediation

git.kernel.org https://git.kernel.org/stable/c/28c8fb7ae2ad27d81c8de3c4fe608c509f6a18aa

Patch
git.kernel.org https://git.kernel.org/stable/c/4013aef2ced9b756a410f50d12df9ebe6a883e4a

Patch
git.kernel.org https://git.kernel.org/stable/c/5ab0ec206deb99eb3baf8f1d7602aeaa91dbcc85

Patch
git.kernel.org https://git.kernel.org/stable/c/a6f0f8873cc30fd4543b09adf03f7f51d293f0e6

Patch
git.kernel.org https://git.kernel.org/stable/c/ced94e137e6cd5e79c65564841d3b7695d0f5fa3

Patch
git.kernel.org https://git.kernel.org/stable/c/e80ff23ba8bdb0f41a1afe2657078e4097d13a9a

Patch
git.kernel.org https://git.kernel.org/stable/c/f299353e7ccbcc5c2ed8993c48fbe7609cbe729a

Patch
git.kernel.org https://git.kernel.org/stable/c/fbd4cf7ee4db65ef36796769fe978e9eba6f0de4

Patch