CVE-2021-21706

ZipArchive::extractTo may extract outside of destination dir

At a glance

Severity: MEDIUM 5.3
EPSS: EPSS 1.44 % · percentile 73 (2026-10-27)
State: PUBLISHED
Published: 2021-10-04
Updated: 2024-09-16
Assigner: php
NVD status: Modified

Description

In PHP versions 7.3.x below 7.3.31, 7.4.x below 7.4.24 and 8.0.x below 8.0.11, in Microsoft Windows environment, ZipArchive::extractTo may be tricked into writing a file outside target directory when extracting a ZIP file, thus potentially causing files to be created or overwritten, subject to OS permissions.

Scores

Version	Score	Vector	Scored by
CVSS 3.1	MEDIUM 5.3	CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N	php
CVSS 3.1	MEDIUM 5.3	CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N	NVD · security@php.net (Secondary)
CVSS 3.1	MEDIUM 6.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N	NVD · nvd@nist.gov (Primary)
CVSS 2.0	MEDIUM 4.3	AV:N/AC:M/Au:N/C:N/I:P/A:N	NVD · nvd@nist.gov (Primary)

Weaknesses (CWE)

European references

ENISA EUVD · EUVD-2021-8878
GCVE · GCVE-0-2021-21706

CERT-FR advisories

CERTFR-2021-AVI-731 — Multiples vulnérabilités dans PHP · cert.ssi.gouv.fr

Affected configurations (NVD CPE)

cpe:2.3:a:php:php:*:*:*:*:*:*:*:* ≥ 7.3.0 < 7.3.31
cpe:2.3:a:php:php:*:*:*:*:*:*:*:* ≥ 7.4.0 < 7.4.24
cpe:2.3:a:php:php:*:*:*:*:*:*:*:* ≥ 8.0.0 < 8.0.11

Affected products

Product	Versions
PHP Group · PHP	affected 7.3.x < 7.3.31 ; affected 7.4.x < 7.4.24 ; affected 8.0.X < 8.0.11

References

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)	Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD