CVE-2021-21707
MEDIUMEPSS 98th pctlDescription
In PHP versions 7.3.x below 7.3.33, 7.4.x below 7.4.26 and 8.0.x below 8.0.13, certain XML parsing functions, like simplexml_load_file(), URL-decode the filename passed to them. If that filename contains URL-encoded NUL character, this may cause the function to interpret this as the end of the filename, thus interpreting the filename differently from what the user intended, which may lead it to reading a different file than intended.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Exploit Intelligence
Very high risk: more likely to be exploited than 98% of all known CVEs.
References
Related Vulnerabilities
Other CWE-159 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2019-9505 | Critical | 9.8 | 3.5% | - | - |
| CVE-2020-1653 | High | 7.5 | 1.6% | - | - |
| CVE-2020-1648 | High | 7.5 | 1.3% | - | - |
| CVE-2020-1646 | High | 7.5 | 1.0% | - | - |
| CVE-2020-29022 | Medium | 5.3 | 0.8% | - | Fix |
| CVE-2026-2636 | Medium | 5.5 | 0.4% | - | - |
Embed a live status badge for CVE-2021-21707
Markdown
[](https://tridentstack.com/cve/CVE-2021-21707)HTML
<a href="https://tridentstack.com/cve/CVE-2021-21707"><img src="https://tridentstack.com/cve/badge/CVE-2021-21707.svg" alt="CVE-2021-21707"></a>Find and fix vulnerabilities across your fleet
TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.
This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.