CVE-2021-21702 - CVE House
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Status published Medium CVE-2021-21702

Null Dereference in SoapClient

Vulnerability Description

In PHP versions 7.3.x below 7.3.27, 7.4.x below 7.4.15 and 8.0.x below 8.0.2, when using SOAP extension to connect to a SOAP server, a malicious SOAP server could return malformed XML data as a response that would cause PHP to access a null pointer and thus cause a crash.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • Reported by jgalindo at datto dot com

References

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Affected Vendor

Affected Software

PHP
Vulnerable Versions:
7.3.x, 7.4.x, 8.0.X

Timeline

Official Publish: February 15th, 2021
Last Modified: September 16th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Weaknesses (CWE)

CWE-476

MITRE ATT&CK TTPs

T1499 Endpoint Denial of Service
Impact
T1499.004 Application or System Exploitation
Impact
T1489 Service Stop
Impact
T1203 Exploitation for Client Execution
Execution
T1190 Exploit Public-Facing Application
Initial Access