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.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | php7.2 | 7.2.10-0ubuntu0.18.04.1 | USN-4279-1, USN-3766-1 |
| Ubuntu 16.04 LTS | php7.0 | 7.0.32-0ubuntu0.16.04.1 | USN-4279-1, USN-3766-1 |
| Ubuntu 14.04 LTS | php5 | 5.5.9+dfsg-1ubuntu4.26 | USN-3766-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 16.04 LTS | php7.0 | 7.0.33-0ubuntu0.16.04.16+esm3 | USN-5300-1 |
| Ubuntu Pro 14.04 LTS | php5 | 5.5.9+dfsg-1ubuntu4.29+esm10 | USN-4279-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP1 | php7 | 7.2.5-4.89.4 | SUSE-SU-2022:4067-1, SUSE-SU-2022:0679-1 |
| SLES 15 | php7 | 7.2.5-4.89.4 | SUSE-SU-2022:4067-1, SUSE-SU-2022:0679-1 |
| SLES 12 SP5 | php72 | 7.2.5-1.75.1 | SUSE-SU-2022:0577-1 |
| SLES 12 | php72 | 7.2.5-1.75.1 | SUSE-SU-2022:0577-1 |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP1 | php7 | 7.2.5-4.89.4 | SUSE-SU-2022:4067-1, SUSE-SU-2022:0679-1 |
| SLES for SAP 15 | php7 | 7.2.5-4.89.4 | SUSE-SU-2022:4067-1, SUSE-SU-2022:0679-1 |
| SLE HPC 15 SP1 | php7 | 7.2.5-4.89.4 | SUSE-SU-2022:4067-1, SUSE-SU-2022:0679-1 |
| SLE HPC 15 | php7 | 7.2.5-4.89.4 | SUSE-SU-2022:4067-1, SUSE-SU-2022:0679-1 |
| SUSE Enterprise Storage 6 | php7 | 7.2.5-4.89.4 | SUSE-SU-2022:4067-1, SUSE-SU-2022:0679-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.4 | php7 | 7.2.34-150000.4.103.1 | SUSE-SU-2022:4067-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.15 | php7 | 7.2.8-r0 | — |
| Alpine v3.14 | php7 | 7.2.8-r0 | — |
| Alpine v3.13 | php7 | 7.2.8-r0 | — |
| Alpine v3.12 | php7 | 7.2.8-r0 | — |
| Alpine v3.11 | php7 | 7.2.8-r0 | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.10 | php7 | 7.2.8-r0 | — |
| Alpine v3.9 | php7 | 7.2.8-r0 | — |
| Alpine v3.8 | php7 | 7.2.8-r0 | — |
Advisories 6
- USN-5300-1 php7.0 vulnerabilities Ubuntu Security Notices (USN) · Jun 25, 2026
- USN-4279-1 php5, php7.0, php7.2, php7.3 vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- USN-3766-1 php5, php7.0, php7.2 vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- SUSE-SU-2022:4067-1 Security update for php7 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2022:0679-1 Security update for php7 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2022:0577-1 Security update for php72 SUSE / openSUSE Security Updates · Feb 4, 2026
References
- https://github.com/php/php-src/blob/PHP-7.1.20/NEWS#L20-L22
- https://bugs.php.net/bug.php?id=70185
- https://bugs.php.net/bug.php?id=75968
- USN-3766-1 vendor-advisory
- https://bugs.php.net/bug.php?id=73342https://github.com/php/php-src/pull/3287
- https://github.com/php/php-src/commit/69dee5c732fe982c82edb17d0dbc3e79a47748d8
- https://www.futureweb.at/security/CVE-2015-9253/
- USN-4279-1 vendor-advisory