Threats / PEAR / CVE-2020-36193
CVE-2020-36193
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
PEAR Archive_Tar vulnerability
PEAR Archive_Tar allows directory traversal via inadequate symbolic link validation during tar extraction, enabling arbitrary file writes on affected systems.
Verdict
Today item — known-exploited.
An attacker can exploit insufficient symlink checking in Archive_Tar to write files outside intended directories during tar operations. This vulnerability has been observed in active exploitation and affects widely-deployed PHP applications including Drupal Core.
01
Is it exploitable?
— the evidence, ranked above the scoreReported exploitation
3 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-08-25).
Probability (EPSS)
EPSS 0.70595 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: PEAR, Archive_Tar. Confirm exact fixed builds in the vendor advisory.
Weakness (CWE)
Mapped to CWE-22 Path Traversal, CWE-59 Link Following — weakness family: Path traversal / file.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I craft a malicious tar archive containing symbolic links that point outside the extraction directory.
Business
Attackers gain ability to overwrite critical application files or inject code into web-accessible locations.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I upload or trigger extraction of the crafted tar file through an application using vulnerable Archive_Tar.
Business
Compromised systems face remote code execution risk, particularly in Drupal and other frameworks relying on PEAR components.
3
Lateral reach — past segmentation narrative 3
Attacker
I achieve arbitrary file write access by bypassing path validation checks during symlink resolution.
Business
System integrity is compromised; attackers can modify configuration, inject backdoors, or escalate privileges across dependent applications.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05