---
id: "CVE-2020-28949"
kind: "vulnerability"
aliases: ["CVE-2020-28949"]
title: "Archive_Tar through 1.4.10 has :// filename sanitization only to address phar attacks, and thus any other\u2026"
severity: "high"
cvss: 7.8
epss: 0.84554
exploited: true
status: "open"
category: "package"
products: [{"name": "PEAR Archive_Tar", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "php archive tar", "fixed": ["1.4.12"], "affected": "< 1.4.12", "ecosystem": "vendor"}, {"name": "debian linux", "fixed": [], "affected": "= 9.0", "ecosystem": "vendor"}, {"name": "debian linux", "fixed": [], "affected": "= 10.0", "ecosystem": "vendor"}, {"name": "fedoraproject fedora", "fixed": [], "affected": "= 32", "ecosystem": "vendor"}, {"name": "fedoraproject fedora", "fixed": [], "affected": "= 33", "ecosystem": "vendor"}, {"name": "fedoraproject fedora", "fixed": [], "affected": "= 34", "ecosystem": "vendor"}, {"name": "fedoraproject fedora", "fixed": [], "affected": "= 35", "ecosystem": "vendor"}, {"name": "drupal", "fixed": ["7.75"], "affected": ">= 7.0, < 7.75", "ecosystem": "vendor"}, {"name": "drupal", "fixed": ["8.9.10"], "affected": ">= 8.0.0, < 8.9.10", "ecosystem": "vendor"}, {"name": "drupal", "fixed": ["8.8.12"], "affected": ">= 8.8.0, < 8.8.12", "ecosystem": "vendor"}, {"name": "drupal", "fixed": ["9.0.9"], "affected": ">= 9.0.0, < 9.0.9", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["archive_tar", "drupal", "exploited", "package", "php", "self-hosted"]
not_affected_if: ["does-not-use-archive_tar", "no-untrusted-archive-input"]
published_at: "2020-11-19T19:15:11+00:00"
first_seen_at: "2026-10-23T19:11:52+00:00"
updated_at: "2026-10-23T22:29:04+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2020-28949", "first_seen_at": "2026-10-23T19:11:52+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2020-28949", "first_seen_at": "2026-10-23T19:13:45+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-28949", "first_seen_at": "2026-10-23T22:29:04+00:00"}]
---

# Archive_Tar through 1.4.10 has :// filename sanitization only to address phar attacks, and thus any other…

PEAR Archive_Tar is a PHP library for reading and writing tar archives, and it fails to block the uppercase PHAR:// stream wrapper while blocking lowercase phar://. An attacker who can get the application to open a crafted archive path can trigger PHP object deserialization and may run code.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:PEAR Archive_Tar affected ? fixed ?
- vendor:php archive tar affected < 1.4.12 fixed 1.4.12
- vendor:debian linux affected = 9.0 fixed ?
- vendor:debian linux affected = 10.0 fixed ?
- vendor:fedoraproject fedora affected = 32 fixed ?
- vendor:fedoraproject fedora affected = 33 fixed ?
- vendor:fedoraproject fedora affected = 34 fixed ?
- vendor:fedoraproject fedora affected = 35 fixed ?
- vendor:drupal affected >= 7.0, < 7.75 fixed 7.75
- vendor:drupal affected >= 8.0.0, < 8.9.10 fixed 8.9.10
- vendor:drupal affected >= 8.8.0, < 8.8.12 fixed 8.8.12
- vendor:drupal affected >= 9.0.0, < 9.0.9 fixed 9.0.9

## Fix

Apply the vendor update per PEAR Archive_Tar instructions; fixed version not stated in the sources.
Upgrade archive_tar to the patched release from Packagist or PEAR; exact version unknown.

## Timeline

- 2026-10-23T19:11:52+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2020-28949
- 2026-10-23T19:13:45+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2020-28949
- 2026-10-23T22:29:04+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2020-28949

## From the sources

PEAR Archive_Tar allows an unserialization attack because phar: is blocked but PHAR: is not blocked. PEAR stands for PHP Extension and Application Repository and it is an open-source framework and distribution system for reusable PHP components with known usage in third-party products such as Drupal Core and Red Hat Linux.

CISA required action: Apply updates per vendor instructions.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_