php: Infinite loop in php-fpm when restarting a child using program execution function
Published Feb 19, 2018
7.5
HIGHCVSS 3.0
EPSS 4.18%
Description
An issue was discovered in PHP 7.3.x before 7.3.0alpha3, 7.2.x before 7.2.8, and before 7.1.20. The php-fpm master process restarts a child process in an endless loop when using program execution functions (e.g., passthru, exec, shell_exec, or system) with a non-blocking STDIN stream, causing this master process to consume 100% of the CPU, and consume disk space with a large volume of error logs, as demonstrated by an attack by a customer of a shared-hosting facility.
Affected products
No data.
No data.
Red Hat Enterprise Linux 5
php
Not affected
Red Hat Enterprise Linux 5
php53
Not affected
Red Hat Enterprise Linux 6
php
Not affected
Red Hat Enterprise Linux 7
php
Not affected
Red Hat Enterprise Linux 8
php
Not affected
Red Hat Software Collections
rh-php56-php
Not affected
Red Hat Software Collections
rh-php70-php
Not affected
Red Hat Software Collections
rh-php71-php
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | php | Not affected | n/a |
| Red Hat Enterprise Linux 5 | php53 | Not affected | n/a |
| Red Hat Enterprise Linux 6 | php | Not affected | n/a |
| Red Hat Enterprise Linux 7 | php | Not affected | n/a |
| Red Hat Enterprise Linux 8 | php | Not affected | n/a |
| Red Hat Software Collections | rh-php56-php | Not affected | n/a |
| Red Hat Software Collections | rh-php70-php | Not affected | n/a |
| Red Hat Software Collections | rh-php71-php | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
The Red Hat Product Security Team does not consider this issue as a security flaw because specially crafted PHP scripts (containing embedded operating system commands) are required to trigger this flaw.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
1 other source (Red Hat) ▾
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
AV:N/AC:L/Au:S/C:N/I:N/A:C
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (15 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 4.18% (0.04176) | 90.59th | v5 (v2026.06.15) |
| Jun 15, 2026 | 4.32% (0.04322) | 89.88th | v5 (v2026.06.15) |
| Nov 20, 2025 | 2.96% (0.02956) | 85.23th | v4 (v2025.03.14) |
| Mar 30, 2025 | 1.43% (0.01432) | 78.87th | v4 (v2025.03.14) |
| Mar 29, 2025 | 3.12% (0.03124) | 77.96th | v4 (v2025.03.14) |
| Mar 17, 2025 | 1.43% (0.01432) | 79.32th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.58% (0.00584) | 78.87th | v3 (v2023.03.01) |
| Apr 11, 2024 | 0.58% (0.00584) | 77.85th | v3 (v2023.03.01) |
| Jan 30, 2024 | 0.58% (0.00584) | 75.83th | v3 (v2023.03.01) |
| Jul 13, 2023 | 0.59% (0.00593) | 75.45th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.65% (0.00648) | 76.15th | v3 (v2023.03.01) |
| Mar 6, 2023 | 2.65% (0.02654) | 82.23th | v2 (v2022.01.01) |
| Nov 16, 2022 | 2.65% (0.02654) | 81.66th | v2 (v2022.01.01) |
| Apr 1, 2022 | 2.58% (0.02583) | 80.29th | v2 (v2022.01.01) |
| Feb 4, 2022 | 2.58% (0.02583) | 61.78th | v2 (v2022.01.01) |
References (12)
- https://access.redhat.com/security/cve/CVE-2015-9253 Vendor Advisory
- https://bugs.php.net/bug.php?id=70185 x_refsource_MISCExploitIssue TrackingVendor Advisory
- https://bugs.php.net/bug.php?id=73342https://github.com/php/php-src/pull/3287 x_refsource_CONFIRMExploitIssue TrackingVendor Advisory
- https://bugs.php.net/bug.php?id=75968 x_refsource_MISCExploitIssue TrackingVendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1547725 Issue Tracking
- https://github.com/php/php-src/blob/PHP-7.1.20/NEWS#L20-L22 x_refsource_CONFIRMThird Party Advisory
- https://github.com/php/php-src/commit/69dee5c732fe982c82edb17d0dbc3e79a47748d8 x_refsource_CONFIRMPatchThird Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2015-9253
- https://usn.ubuntu.com/3766-1/ vendor-advisoryx_refsource_UBUNTUThird Party Advisory
- https://usn.ubuntu.com/4279-1/ vendor-advisoryx_refsource_UBUNTU
- https://www.cve.org/CVERecord?id=CVE-2015-9253
- https://www.futureweb.at/security/CVE-2015-9253/ x_refsource_MISCExploitThird Party Advisory
Change history (0)
No recorded changes yet.