CVE-2025-38528Public exploit

Kernel warning via malformed BPF format parsing

Published Aug 16, 2025 · Updated Aug 5, 2026

Improper BPF format validation in Linux 5.13 allows local users to trigger a kernel warning with a crafted helper format string. bpf_bprintf_prepare skips the punctuation percent sign after %p, leaving format_decode to process an unsupported percent-NUL sequence. Loading the triggering BPF program requires local BPF access; systems configured to panic on warnings can suffer a service interruption.

CVSS severity5.5
Medium
EPSS probability0.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper BPF format validation in Linux 5.13 allows local users to trigger a kernel warning with a crafted helper format string. bpf_bprintf_prepare skips the punctuation percent sign after %p, leaving format_decode to process an unsupported percent-NUL sequence. Loading the triggering BPF program requires local BPF access; systems configured to panic on warnings can suffer a service interruption.

The record

CVE
CVE-2025-38528
Published
Aug 16, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 16, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=48cac3f4a96ddf08df8e53809ed066de0dc93915 <1c5f5fd47bbda17cb885fe6f03730702cd53d3f8
  2. Affected versionversion=48cac3f4a96ddf08df8e53809ed066de0dc93915 <61d5fa45ed13e42af14c7e959baba9908b8ee6d4
  3. Affected versionversion=48cac3f4a96ddf08df8e53809ed066de0dc93915 <6952aeace93f8c9ea01849efecac24dd3152c9c9
  4. Affected versionversion=48cac3f4a96ddf08df8e53809ed066de0dc93915 <97303e541e12f1fea97834ec64b98991e8775f39
  5. Affected versionversion=48cac3f4a96ddf08df8e53809ed066de0dc93915 <e7be679124bae8cf4fa6e40d7e1661baddfb3289
  6. Affected versionversion=48cac3f4a96ddf08df8e53809ed066de0dc93915 <f8242745871f81a3ac37f9f51853d12854fd0b58
  7. Affected versionversion=5.13

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=48cac3f4a96ddf08df8e53809ed066de0dc93915 <1c5f5fd47bbda17cb885fe6f03730702cd53d3f8; version=48cac3f4a96ddf08df8e53809ed066de0dc93915 <61d5fa45ed13e42af14c7e959baba9908b8ee6d4; version=48cac3f4a96ddf08df8e53809ed066de0dc93915 <6952aeace93f8c9ea01849efecac24dd3152c9c9; version=48cac3f4a96ddf08df8e53809ed066de0dc93915 <97303e541e12f1fea97834ec64b98991e8775f39; version=48cac3f4a96ddf08df8e53809ed066de0dc93915 <e7be679124bae8cf4fa6e40d7e1661baddfb3289; version=48cac3f4a96ddf08df8e53809ed066de0dc93915 <f8242745871f81a3ac37f9f51853d12854fd0b58; version=5.13

Published CVSS scores

5.5TuxCareCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1499Endpoint Denial of Service

Public exploit references

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Technologies

Your stack

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Your stack

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