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Fencer Vulns
high 7.5

CVE-2009-4018 in the critical feed json

The proc_open function in ext/standard/proc_open.c in PHP before 5.2.11 and 5.3.x before 5.3.1 does not enforce the (1) safe_mode_allowed_e…

published 2009-11-27 16 y ago modified 2026-06-16 4 mo ago also EUVD-2009-3989

cvss
7.5
version 2.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
11.3%
EPSS 11.3% chance of exploitation in 30 days, percentile 96%
public exploits
1
Exploit-DB

Summary

The proc_open function in ext/standard/proc_open.c in PHP before 5.2.11 and 5.3.x before 5.3.1 does not enforce the (1) safe_mode_allowed_env_vars and (2) safe_mode_protected_env_vars directives, which allows context-dependent attackers to execute programs with an arbitrary environment via the env parameter, as demonstrated by a crafted value of the LD_LIBRARY_PATH environment variable.

Patch / fix

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2009-4018 updated cvss 3.3

php: proc_open() safe mode restriction bypass

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Timeline

  1. Published
  2. First public exploit (EDB-11636)

Exploit prediction

11.34% chance of exploitation in the next 30 days, higher than 96% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • EDB-11636 Kolang 4.3.10 < 5.3.0 - 'proc_open()' PHP 'safe_mode' Bypass webapps, 2010-03-05
  • bugs.php.net http://bugs.php.net/bug.php?id=49026 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 2.0 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P

Classification

Weakness
  • CWE-264 Permissions, Privileges, and Access Controls
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.