CVE-2025-38591Buffer Access with Incorrect Length Value in Linux

Severity
5.5MEDIUMNVD
EPSS
0.0%
top 98.92%
CISA KEV
Not in KEV
Exploit
No known exploits
Timeline
PublishedAug 19
Latest updateApr 17

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Reject narrower access to pointer ctx fields The following BPF program, simplified from a syzkaller repro, causes a kernel warning: r0 = *(u8 *)(r1 + 169); exit; With pointer field sk being at offset 168 in __sk_buff. This access is detected as a narrower read in bpf_skb_is_valid_access because it doesn't match offsetof(struct __sk_buff, sk). It is therefore allowed and later proceeds to bpf_convert_ctx_access. Note tha

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitability: 1.8 | Impact: 3.6

Patches

🔴Vulnerability Details

2
OSV
CVE-2025-38591: In the Linux kernel, the following vulnerability has been resolved: bpf: Reject narrower access to pointer ctx fields The following BPF program, simpl2025-08-19
GHSA
GHSA-cgjw-h652-c9q2: In the Linux kernel, the following vulnerability has been resolved: bpf: Reject narrower access to pointer ctx fields The following BPF program, sim2025-08-19

📋Vendor Advisories

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