CVE-2018-6623: An issue was discovered in Hola 1.79.859

This month

HIGH 8.8DOWNGRADE

CVE-2018-6623 is a high-severity flaw (CVSS 8.8) affecting vpn. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

An issue was discovered in Hola 1.79.859. An unprivileged user could modify or overwrite the executable with arbitrary code, which would be executed the next time the service is started. Depending on the user that the service runs as, this could result in privilege escalation. The issue exists because of the SERVICE_ALL_ACCESS access right for the hola_svc and hola_updater services.

Why this priority

High severity

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	8.8 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.8% (top 42%)
CISA exploited list	No
Weakness	CWE-732
Published	2018-03-12
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: hola

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2018-03-12 21:29 UTCPublished CVE record published
2026-06-17 02:02 UTCUpdated Record last modified

hola vpn DOWNGRADE

Affected: 1.79.859

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.79.859

1. Check installed version

apt-cache policy vpn || rpm -q vpn || vpn --version

2. No fixed release: DOWNGRADE to a release before 1.79.859 (Debian / Ubuntu)

apt-cache madison vpn sudo apt install vpn=<VERSION_BEFORE_1.79.859> sudo apt-mark hold vpn

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list vpn sudo dnf downgrade vpn-<VERSION_BEFORE_1.79.859> sudo dnf versionlock add vpn

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2018-6623?

vpn: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2018-6623 being exploited?

CVE-2018-6623 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2018-6623 affect?

CVE-2018-6623 affects vpn. Severity is high (CVSS 8.8). An issue was discovered in Hola 1.79.859. An unprivileged user could modify or overwrite the executable with arbitrary code, which would be executed the next time the service is started. Depending on the user that the service runs as, this

How urgent is CVE-2018-6623?

Priority 45/100. High severity

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References

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