SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2025-38528

In the Linux kernel, the following vulnerability has been resolved: bpf: Reject %p% format string in bprintf-like helpers static const char fmt[] = "%p%"; bpf_trace_printk(fmt, sizeof(fmt)); The above BPF program isn't rejected and causes a kernel…

MEDIUM 5.5EPSS 0.17%

Does this matter?

Lower severity and a low EPSS score (0.17%). Track it; it rarely justifies an emergency change on its own.

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Reject %p% format string in bprintf-like helpers static const char fmt[] = "%p%"; bpf_trace_printk(fmt, sizeof(fmt)); The above BPF program isn't rejected and causes a kernel warning at runtime: Please remove unsupported %\x00 in format string WARNING: CPU: 1 PID: 7244 at lib/vsprintf.c:2680 format_decode+0x49c/0x5d0 This happens because bpf_bprintf_prepare skips over the second %, detected as punctuation, while processing %p. This patch fixes it by not skipping over punctuation. %\x00 is then processed in the next iteration and rejected.

CVSS 3.1
5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS
0.17% probability · 7th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Affected
linux/linux kernel · debian/debian linux
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
EPSS trend
0%3%5%27 October 2026: 0.17%27 October 202627 October 2026

EPSS 0.2% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.