PHP up to 7.9 Environment Variable php_cli_server.c php_cli_server_startup_workers PHP_CLI_SERVER_WORKERS heap-based overflow

CVSS Meta Temp Score
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CTI Interest Score
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5.2$0-$5k0.00

Summaryinfo

A vulnerability was found in PHP. It has been classified as critical. This impacts the function php_cli_server_startup_workers of the file sapi/cli/php_cli_server.c of the component Environment Variable Handler. The manipulation of the argument PHP_CLI_SERVER_WORKERS leads to heap-based overflow. This vulnerability is referenced as CVE-2022-4900. The attack can only be performed from a local environment. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in PHP (Programming Language Software). This issue affects the function php_cli_server_startup_workers of the file sapi/cli/php_cli_server.c of the component Environment Variable Handler. The manipulation of the argument PHP_CLI_SERVER_WORKERS with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). Impacted is confidentiality, integrity, and availability. The summary by CVE is:

A vulnerability was found in PHP where setting the environment variable PHP_CLI_SERVER_WORKERS to a large value leads to a heap buffer overflow.

The weakness was published 04/22/2023. The advisory is shared at github.com. The identification of this vulnerability is CVE-2022-4900 since 01/31/2023. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 208984 (Debian dla-3920 : libapache2-mod-php7.4 - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 8.0 eliminates this vulnerability. Applying the patch 789a37f14405e2d1a05a76c9fb4ed2d49d4580d5 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (208984). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.2
VulDB Meta Temp Score: 5.2

VulDB Base Score: 4.0
VulDB Temp Score: 3.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CNA Base Score: 6.2
CNA Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 208984
Nessus Name: Debian dla-3920 : libapache2-mod-php7.4 - security update

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: PHP 8.0
Patch: 789a37f14405e2d1a05a76c9fb4ed2d49d4580d5

Timelineinfo

01/31/2023 🔍
04/22/2023 +80 days 🔍
04/22/2023 +0 days 🔍
04/27/2025 +736 days 🔍

Sourcesinfo

Product: php.org

Advisory: github.com
Status: Confirmed

CVE: CVE-2022-4900 (🔍)
GCVE (CVE): GCVE-0-2022-4900
GCVE (VulDB): GCVE-100-227225

Entryinfo

Created: 04/22/2023 17:44
Updated: 04/27/2025 04:00
Changes: 04/22/2023 17:44 (43), 10/15/2024 06:56 (18), 11/19/2024 22:44 (22), 04/27/2025 04:00 (3)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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