CVE-2021-21702: Null Dereference in SoapClient

Published Feb 1, 2021
·
Updated

Fixed bug (Null Dereference in SoapClient). (CVE-2021-21702)

Other sources

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.

Affected Software

11 affected componentsFixes available
debian/php7.3
7.3.31-1~deb10u17.3.31-1~deb10u5
debian/php7.4
7.4.33-1+deb11u4
PHP PHP<8.0.2
8.0.2
PHP PHP>=7.3.0<7.3.27
PHP PHP>=7.4.0<7.4.15
PHP PHP>=8.0.0<8.0.2
Debian Debian Linux=9.0
Debian Debian Linux=10.0
NetApp Clustered Data ONTAP
Oracle Communications Diameter Signaling Router>=8.0.0<=8.5.0
Microsoft cbl2 php

Event History

Feb 4, 2021
CVE Published
via PHP·12:00 AM
Feb 15, 2021
CVE Published
via MITRE·04:10 AM
Data Sourced
via MITRE·04:10 AM
DescriptionSeverityWeakness
Oct 1, 2025
Data Sourced
via Microsoft·11:11 PM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·11:11 PM
Affected Software
Updated
via Microsoft·11:11 PM
DescriptionSeverity
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Frequently Asked Questions

1

What is the vulnerability ID for this bug?

The vulnerability ID for this bug is CVE-2021-21702.

2

What is the title of this bug?

The title of this bug is 'Fixed bug (Null Dereference in SoapClient). (CVE-2021-21702)'

3

What is the description of this bug?

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.

4

What is the severity of CVE-2021-21702?

The severity of CVE-2021-21702 is high with a CVSS score of 7.5.

5

How can I fix CVE-2021-21702?

To fix CVE-2021-21702, update PHP to version 8.0.2 if you are using PHP 8.0.x, and update to the latest available versions if you are using PHP 7.3.x or 7.4.x.

6

Where can I find more information about CVE-2021-21702?

You can find more information about CVE-2021-21702 at the following references: [link1], [link2], [link3].

Contact

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