CVE-2018-6634: A vulnerability in Parsec Windows 142-0 and Parsec 'Linux Ubuntu 16.04 LTS Desktop' Build 142-1 allows unautho

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CRITICAL 9.8REMOTEWATCHLISTDOWNGRADE

CVE-2018-6634 is a critical-severity flaw (CVSS 9.8) affecting parsec. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A vulnerability in Parsec Windows 142-0 and Parsec 'Linux Ubuntu 16.04 LTS Desktop' Build 142-1 allows unauthorized users to maintain access to an account.

Why this priority

Critical severity
Remotely exploitable, no login, no user action
On your watchlist

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

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	1.5% (top 26%)
CISA exploited list	No
Weakness	CWE-613
Published	2019-05-07
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: parsecgaming

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

Am I affected?

Timeline

2019-05-07 20:29 UTCPublished CVE record published
2026-06-17 02:02 UTCUpdated Record last modified

parsecgaming parsec DOWNGRADE

Affected: 142-0 · 142-1

Fixed in: no fixed release known

Safe to downgrade to: a release before 142-0

1. Check installed version

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

2. No fixed release: DOWNGRADE to a release before 142-0 (Debian / Ubuntu)

apt-cache madison parsec sudo apt install parsec=<VERSION_BEFORE_142-0> sudo apt-mark hold parsec

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

dnf --showduplicates list parsec sudo dnf downgrade parsec-<VERSION_BEFORE_142-0> sudo dnf versionlock add parsec

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-2018-6634?

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

Is CVE-2018-6634 being exploited?

CVE-2018-6634 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-2018-6634 affect?

CVE-2018-6634 affects parsec. Severity is critical (CVSS 9.8). A vulnerability in Parsec Windows 142-0 and Parsec 'Linux Ubuntu 16.04 LTS Desktop' Build 142-1 allows unauthorized users to maintain access to an account.

How urgent is CVE-2018-6634?

Priority 63/100. Critical severity; Remotely exploitable, no login, no user action; On your watchlist

Software pages

Windows vulnerabilities · Ubuntu vulnerabilities

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References

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