CVE-2024-9026Public exploit

Log tampering via incorrect flush-marker offset

Published Oct 8, 2024 · Updated Nov 3, 2025

Log injection in PHP-FPM 8.1.0 through 8.1.29, 8.2.0 through 8.2.23, and 8.3.0 through 8.3.11 allows local users to alter logs. In fpm_stdio_child_said, a split FPM_STDIO_CMD_FLUSH match advances the input start by the partial-match position rather than the marker bytes consumed, inserting marker bytes or deleting up to four message characters. The flaw requires catch_workers_output to be enabled and control of worker stdout or stderr; syslog also truncates content after an injected NUL.

CVSS severity3.3
Low
EPSS probability0.49%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Log injection in PHP-FPM 8.1.0 through 8.1.29, 8.2.0 through 8.2.23, and 8.3.0 through 8.3.11 allows local users to alter logs. In fpm_stdio_child_said, a split FPM_STDIO_CMD_FLUSH match advances the input start by the partial-match position rather than the marker bytes consumed, inserting marker bytes or deleting up to four message characters. The flaw requires catch_workers_output to be enabled and control of worker stdout or stderr; syslog also truncates content after an injected NUL.

The record

CVE
CVE-2024-9026
Published
Oct 8, 2024
Updated
Nov 3, 2025
Vendor
The PHP Group
Product
PHP
Classifications
CWE-117, CWE-158, T1070.002
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 8, 2024CVE publishedPublication date reported by the CVE source.
  2. Nov 3, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=8.1.0 <8.1.30
  2. Affected versionversion=8.1.* <8.1.30
  3. Affected versionversion=8.2.0 <8.2.24
  4. Affected versionversion=8.2.* <8.2.24
  5. Affected versionversion=8.3.0 <8.3.12
  6. Affected versionversion=8.3.* <8.3.12

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The PHP Group · PHPversion=8.1.0 <8.1.30; version=8.1.* <8.1.30; version=8.2.0 <8.2.24; version=8.2.* <8.2.24; version=8.3.0 <8.3.12; version=8.3.* <8.3.12

Published CVSS scores

3.3PHP GroupCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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

CWE-117Improper Output Neutralization for Logs
CWE-158Improper Neutralization of Null Byte or NUL Character
T1070.002Clear Linux or Mac System Logs

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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