What’s Vulnerable › Vulnerabilities

CVE-2021-21702: Null Dereference in SoapClient

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 3.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-02-15 · updated 2026-06-17
• Weakness: CWE-476

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.

Affected products

• Debian Linux: 9.0, 10.0
• Clustered Data ONTAP: all versions
• Oracle Corporation Communications Diameter Signaling Router (DSR): from 8.0.0 through 8.5.0
• PHP: from 7.3.0 before 7.3.27; from 7.4.0 before 7.4.15; from 8.0.0 before 8.0.2 — fixed in 7.3.27, 7.4.15, 8.0.2

How to fix

Upgrade to a fixed version: PHP 7.3.27, 7.4.15, 8.0.2. Check the vendor advisory for mitigations.

References

• https://bugs.php.net/bug.php?id=80672
• https://lists.debian.org/debian-lts-announce/2021/07/msg00008.html
• https://security.gentoo.org/glsa/202105-23
• https://security.netapp.com/advisory/ntap-20210312-0005/
• https://www.debian.org/security/2021/dsa-4856
• https://www.oracle.com/security-alerts/cpuoct2021.html
• https://www.tenable.com/security/tns-2021-14
• https://bugs.php.net/bug.php?id=80672
• https://lists.debian.org/debian-lts-announce/2021/07/msg00008.html
• https://security.gentoo.org/glsa/202105-23
• https://security.netapp.com/advisory/ntap-20210312-0005/
• https://www.debian.org/security/2021/dsa-4856

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