Verification check bypass in Gate One

published 2021-10-06 5y ago modified 2026-06-17 4mo ago also GHSA-q6j2-g8qf-wvf7 , PYSEC-2021-423 , EUVD-2021-0090

cvss: 5.3; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.8%; EPSS 0.8% chance of exploitation in 30 days, percentile 56%
public exploits: 0; none known

An issue in Gate One 1.2.0 allows attackers to bypass to the verification check done by the origins list and connect to Gate One instances used by hosts not on the origins list.

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Exploit prediction

0.79% chance of exploitation in the next 30 days, higher than 56% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

github.com https://github.com/liftoff/GateOne/issues/728 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:P/A:N
GitHub	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected packages

ecosystem	package	affected	fixed in
pypi	gateone	<=1.2.0 all versions	no fix listed

Classification

Weakness

CWE-290 Authentication Bypass by Spoofing

References

github.com /liftoff/GateOne/issues/728
web, exploit, issue-tracking, third-party-advisory, report
cwe.mitre.org /data/definitions/290.html
technical-description
nvd.nist.gov /vuln/detail/CVE-2020-19003
advisory
github.com /advisories/GHSA-q6j2-g8qf-wvf7
advisory
github.com /liftoff/GateOne
package
github.com /pypa/advisory-database/tree/main/vulns/gateone/PYSEC-2021-423.yaml
web

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.