Threats / PEAR / CVE-2020-28949
CVE-2020-28949
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
PEAR Archive_Tar vulnerability
PEAR Archive_Tar contains an unserialization vulnerability due to incomplete case-sensitive blocking of the phar: protocol wrapper, allowing attackers to bypass restrictions via the uppercase PHAR: variant.
Verdict
Today item — known-exploited.
An attacker can exploit case-sensitivity in protocol filtering to trigger unsafe unserialization of malicious PHAR archives, potentially achieving remote code execution on systems using affected PEAR Archive_Tar versions.
01
Is it exploitable?
— the evidence, ranked above the scoreExploit available
Public proof-of-concept exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported 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 0.84554 — 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-74 CWE-74 — weakness family: Injection.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 PHAR archive and reference it using the uppercase PHAR: protocol wrapper to bypass the lowercase phar: filter.
Business
Attackers gain code execution capability on web servers and applications relying on Archive_Tar, compromising confidentiality, integrity, and availability.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I upload or inject the bypassed PHAR archive into an application that processes tar files without proper validation.
Business
Third-party products like Drupal Core and systems running Red Hat Linux become vulnerable to remote exploitation through their dependency on PEAR components.
3
Lateral reach — past segmentation narrative 3
Attacker
I trigger unserialization of the malicious payload during archive extraction or processing.
Business
Organizations face operational disruption, data theft, and potential lateral movement within infrastructure due to compromised application servers.
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