PHP up to 7.1.32 FPM fpm_main.c env_path_info Underflow out-of-bounds write

CVSS Meta Temp Score
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CTI Interest Score
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8.5$0-$5k0.00

Summaryinfo

A vulnerability has been found in PHP up to 7.1.32 and classified as critical. Affected is the function env_path_info of the file fpm_main.c of the component FPM. Performing a manipulation results in out-of-bounds write (Underflow). This vulnerability is identified as CVE-2019-11043. The attack can be initiated remotely. Additionally, an exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in PHP up to 7.1.32 (Programming Language Software). It has been classified as critical. This affects the function env_path_info of the file fpm_main.c of the component FPM. The manipulation with an unknown input leads to a out-of-bounds write vulnerability (Underflow). CWE is classifying the issue as CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In PHP versions 7.1.x below 7.1.33, 7.2.x below 7.2.24 and 7.3.x below 7.3.11 in certain configurations of FPM setup it is possible to cause FPM module to write past allocated buffers into the space reserved for FCGI protocol data, thus opening the possibility of remote code execution.

The weakness was released 10/24/2019 as Version 7.1.33 as confirmed changelog (Website). It is possible to read the advisory at php.net. This vulnerability is uniquely identified as CVE-2019-11043. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details and a public exploit are known.

After 2 days, there has been an exploit disclosed. The exploit is shared for download at bugs.php.net. It is declared as attacked. We expect the 0-day to have been worth approximately $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 236657 (Alibaba Cloud Linux 3 : 0049: php:7.4 (ALINUX3-SA-2022:0049)), which helps to determine the existence of the flaw in a target environment. The CISA Known Exploited Vulnerabilities Catalog lists this issue since 03/25/2022 with a due date of 04/15/2022:

Apply updates per vendor instructions.

Upgrading to version 7.1.33 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Exploit-DB (48182) and Tenable (236657). Further details are available at bugs.php.net. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.6
VulDB Meta Temp Score: 8.5

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CNA Base Score: 8.7
CNA Vector (PHP Group): 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Name: Underflow
Class: Out-of-bounds write / Underflow
CWE: CWE-787 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Attacked
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

KEV Added: 🔍
KEV Due: 🔍
KEV Remediation: 🔍
KEV Ransomware: 🔍
KEV Notice: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 236657
Nessus Name: Alibaba Cloud Linux 3 : 0049: php:7.4 (ALINUX3-SA-2022:0049)

Exploit-DB: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍
Exploit Delay Time: 🔍

Upgrade: PHP 7.1.33

Timelineinfo

04/09/2019 🔍
10/24/2019 +198 days 🔍
10/24/2019 +0 days 🔍
10/26/2019 +2 days 🔍
10/26/2019 +0 days 🔍
08/04/2025 +2109 days 🔍

Sourcesinfo

Product: php.org

Advisory: Version 7.1.33
Status: Confirmed

CVE: CVE-2019-11043 (🔍)
GCVE (CVE): GCVE-0-2019-11043
GCVE (VulDB): GCVE-100-144231
scip Labs: https://www.scip.ch/en/?labs.20161013
Misc.: 🔍

Entryinfo

Created: 10/26/2019 15:59
Updated: 08/04/2025 05:23
Changes: 10/26/2019 15:59 (50), 10/26/2019 16:04 (17), 01/29/2024 09:41 (4), 01/29/2024 09:46 (12), 04/24/2024 16:09 (27), 07/17/2024 13:04 (1), 09/09/2024 22:29 (1), 05/18/2025 20:31 (2), 08/04/2025 05:23 (1)
Complete: 🔍
Submitter: misc
Cache ID: 216::103

Submitinfo

Accepted

  • Submit #110: PHP-FPM env_path_info underflow in fpm_main.c can lead to RCE (by misc)

Be aware that VulDB is the high quality source for vulnerability data.

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