CVE Tools
Sign in

CVE-2016-20021

Published: Jan 12, 2024Updated: Jun 3, 2025 Sources: CVE List NVD GHSACWE-347
NVD MITRE
9.8CVSSCRITICAL
EPSS Score
0.5%
Top 63.4%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

In Gentoo Portage before 3.0.47, there is missing PGP validation of executed code: the standalone emerge-webrsync downloads a .gpgsig file but does not perform signature verification. Unless emerge-webrsync is used, Portage is not vulnerable.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-347

Affected Products

n/an/a
portagegentoo
On-prem
Operating Systems / linux-distro
portagePyPIOSS Libraries
gentoooss-projectUSOperating Systemsaka gentoo linux
pypipackage-ecosystemOSS Libraries

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

https://wiki.gentoo.org/wiki/Portage
wiki.gentoo.org
https://gitweb.gentoo.org/proj/portage.git/tree/NEWS
gitweb.gentoo.org
https://bugs.gentoo.org/597800
bugs.gentoo.org
and 5 more references View all →

Timeline

Published
Jan 12, 2024
Last Updated
Jun 3, 2025

Unlock Complete Vulnerability Intelligence

Get the full picture for CVE-2016-20021 and every CVE in our database. Create a free account — no credit card required.

Create Free Account
Plain-language analysis
Impact assessment and exploitation scenario in plain English
Attack graph visualization
Interactive attack path and kill chain mapping
Exploit details & PoC links
ExploitDB, Metasploit, GitHub PoCs with direct links
Nuclei scanner templates
Ready-to-use vulnerability scanner templates
Full remediation guide
Patch instructions, workarounds, and compliance impact
Interactive AI chat
Ask questions about this vulnerability in natural language
Related vulnerabilities
Semantically similar CVEs and attack patterns
REST API & MCP access
Integrate vulnerability data into your workflows