CVE-2022-4900 | Potential buffer overflow in php_cli_server_startup_workers

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.

Published: 2023-11-02 Last update: 2025-11-03 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2022-4900 is rated Low Risk (35/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.37%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2022-4900

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.07% 0.37% +0.30%
2 2023-12-01 0.04% 0.07% +0.02%
3 2023-11-10 — 0.04% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2022-4900

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.2 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.5 3.6 [email protected]
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 [email protected]

Weakness enumeration for CVE-2022-4900

OS Trackers for CVE-2022-4900

vendor priority summary link
debian unimportant CVE-2022-4900 unimportant priority: Debian including 2 source packages (php7.4, php8.2), 2 status rows across 2 suites (bookworm, bullseye): resolved 2. https://security-tracker.debian.org/tracker/CVE-2022-4900
redhat low — https://access.redhat.com/security/cve/CVE-2022-4900
suse medium CVE-2022-4900 severity moderate: SUSE including 243 source package names (apache2-mod_php7, apache2-mod_php7-7.4.33-150400.4.22.1, …), 564 product×package rows across 19 product lines (SUSE Liberty Linux 8, SUSE Linux Enterprise Module for Legacy 15 SP4, … (19 product lines)): Fixed 414, Known Not Affected 150. https://www.suse.com/security/cve/CVE-2022-4900/
ubuntu low CVE-2022-4900 low priority: Ubuntu including 7 source packages (php5, php7.0, …), 54 status rows across 10 suites (bionic, focal, jammy, kinetic, lunar, mantic, noble, trusty, upstream, xenial): DNE 38, needs-triage 7, not-affected 6, released 2, ignored 1. https://ubuntu.com/security/CVE-2022-4900

Affected software / configurations for CVE-2022-4900

Vendor Product Version Raw CPE
php php < 8.0.22 cpe:2.3:a:php:php:*:*:*:*:*:*:*:*
redhat software_collections — cpe:2.3:a:redhat:software_collections:-:*:*:*:*:*:*:*
redhat enterprise_linux 6.0 cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*
redhat enterprise_linux 7.0 cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
redhat enterprise_linux 9.0 cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*

References for CVE-2022-4900

cvelogic Threat Intelligence