In the Linux kernel, the following vulnerability has been resolved:
bpf: Reject %p% format string in bprintf-like helpers
static const char fmt[] = "%p%"; bpftraceprintk(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 bpfbprintfprepare 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.
{
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/38xxx/CVE-2025-38528.json",
"cna_assigner": "Linux"
}