CVE-2021-26807: GalaxyClient version 2.0.28.9 loads unsigned DLLs such as zlib1.dll, libgcc_s_dw2-1.dll and libwinpthread-1.dl

This month

HIGH 7.8DOWNGRADE

CVE-2021-26807 is a high-severity flaw (CVSS 7.8) affecting galaxy. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

GalaxyClient version 2.0.28.9 loads unsigned DLLs such as zlib1.dll, libgcc_s_dw2-1.dll and libwinpthread-1.dll from PATH, which allows an attacker to potentially run code locally through unsigned DLL loading.

Why this priority

High severity
Public exploit reference

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

Risk facts

CVSS score	7.8 (High)
Attack vector	Local
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.5% (top 59%)
CISA exploited list	No
Weakness	CWE-426
Published	2021-04-30
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: gog

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

Am I affected?

Timeline

2021-04-30 11:15 UTCPublished CVE record published
2026-06-17 03:43 UTCUpdated Record last modified

gog galaxy DOWNGRADE

Affected: 2.0.28.9

Fixed in: no fixed release known

Safe to downgrade to: a release before 2.0.28.9

1. Check installed version

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

2. No fixed release: DOWNGRADE to a release before 2.0.28.9 (Debian / Ubuntu)

apt-cache madison galaxy sudo apt install galaxy=<VERSION_BEFORE_2.0.28.9> sudo apt-mark hold galaxy

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

dnf --showduplicates list galaxy sudo dnf downgrade galaxy-<VERSION_BEFORE_2.0.28.9> sudo dnf versionlock add galaxy

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-2021-26807?

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

Is CVE-2021-26807 being exploited?

CVE-2021-26807 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-2021-26807 affect?

CVE-2021-26807 affects galaxy. Severity is high (CVSS 7.8). GalaxyClient version 2.0.28.9 loads unsigned DLLs such as zlib1.dll, libgcc_s_dw2-1.dll and libwinpthread-1.dll from PATH, which allows an attacker to potentially run code locally through unsigned DLL loading.

How urgent is CVE-2021-26807?

Priority 43/100. High severity; Public exploit reference

Related CVEs

CVE-2024-42351 MEDIUM 6.5 UPGRADE Galaxy is a free, open-source system for analyzing data, authoring workflows, training and education, publishi
CVE-2024-42346 HIGH 7.6 UPGRADE Galaxy is a free, open-source system for analyzing data, authoring workflows, training and education, publishi
CVE-2023-42812 MEDIUM 6.3 UPGRADE Galaxy is an open-source platform for FAIR data analysis
CVE-2023-27578 CRITICAL 9.1 UPGRADE Galaxy is an open-source platform for data analysis
CVE-2022-31262 HIGH 7.8 UPGRADE An exploitable local privilege escalation vulnerability exists in GOG Galaxy 2.0.46

References

← Back to latest CVEs