CVE-2021-28171: The Vangene deltaFlow E-platform does not take properly protective measures

This month

CRITICAL 9.8REMOTEUPGRADE

CVE-2021-28171 is a critical-severity flaw (CVSS 9.8) affecting deltaflow. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

The Vangene deltaFlow E-platform does not take properly protective measures. Attackers can obtain privileged permissions remotely by tampering with users’ data in the Cookie.

Why this priority

Critical severity
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	1.2% (top 31%)
CISA exploited list	No
Weakness	CWE-522, CWE-565
Published	2021-04-06
Last modified	2026-06-17

Publisher (CNA): TWCERT/CC · Vendor: deltaflow project

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

Am I affected?

Timeline

2021-04-06 12:15 UTCPublished CVE record published
2026-06-17 03:45 UTCUpdated Record last modified

deltaflow project deltaflow UPGRADE

Affected: >= 4.0 and < 7.7

Fixed in: 7.7

Safe to downgrade to: a release before 4.0

1. Check installed version

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

2. UPGRADE to 7.7 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade deltaflow

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade deltaflow

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 4.0 (Debian / Ubuntu)

apt-cache madison deltaflow sudo apt install deltaflow=<VERSION_BEFORE_4.0> sudo apt-mark hold deltaflow

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list deltaflow sudo dnf downgrade deltaflow-<VERSION_BEFORE_4.0> sudo dnf versionlock add deltaflow

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-2021-28171?

deltaflow: upgrade to 7.7. Exact commands for each OS are on this page.

Is CVE-2021-28171 being exploited?

CVE-2021-28171 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-2021-28171 affect?

CVE-2021-28171 affects deltaflow. Severity is critical (CVSS 9.8). The Vangene deltaFlow E-platform does not take properly protective measures. Attackers can obtain privileged permissions remotely by tampering with users’ data in the Cookie.

How urgent is CVE-2021-28171?

Priority 56/100. Critical severity; Remotely exploitable, no login, no user action

Related CVEs

CVE-2021-28173 CRITICAL 9.8 UPGRADE The file upload function of Vangene deltaFlow E-platform does not perform access controlled properly
CVE-2021-28172 HIGH 7.5 UPGRADE There is a Path Traversal vulnerability in the file download function of Vangene deltaFlow E-platform

References

← Back to latest CVEs