CVE-2020-21991: AVE DOMINAplus <=1.10.x suffers from an authentication bypass vulnerability due to missing control check when

Q: How urgent is CVE-2020-21991?

Priority 66/100. Critical severity; Public exploit reference; Remotely exploitable, no login, no user action

This week

CRITICAL 9.8REMOTEUPGRADEMITIGATEMITIGATE

CVE-2020-21991 is a critical-severity flaw (CVSS 9.8) affecting dominaplus, 53ab-wbs firmware, ts01 firmware. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

AVE DOMINAplus <=1.10.x suffers from an authentication bypass vulnerability due to missing control check when directly calling the autologin GET parameter in changeparams.php script. Setting the autologin value to 1 allows an unauthenticated attacker to permanently disable the authentication security control and access the management interface with admin privileges without providing credentials.

Why this priority

Critical severity
Public exploit reference
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	2.9% (top 13%)
CISA exploited list	No
Weakness	CWE-287
Published	2021-04-28
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: ave

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

Am I affected?

Timeline

2021-04-28 14:15 UTCPublished CVE record published
2026-06-17 03:04 UTCUpdated Record last modified

ave dominaplus UPGRADE

Affected: >= 1.10.11 and <= 1.10.77

Fixed in: newer than 1.10.77

Safe to downgrade to: a release before 1.10.11

1. Check installed version

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

2. UPGRADE to newer than 1.10.77 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade dominaplus

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 1.10.11 (Debian / Ubuntu)

apt-cache madison dominaplus sudo apt install dominaplus=<VERSION_BEFORE_1.10.11> sudo apt-mark hold dominaplus

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

dnf --showduplicates list dominaplus sudo dnf downgrade dominaplus-<VERSION_BEFORE_1.10.11> sudo dnf versionlock add dominaplus

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.

ave 53ab-wbs firmware MITIGATE

Affected: 1.10.62

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.10.62

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

ave ts01 firmware MITIGATE

Affected: 1.0.65

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.0.65

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

ave ts03x-v firmware MITIGATE

Affected: 1.10.45a

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.10.45a

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

ave ts04x-v firmware MITIGATE

Affected: 1.10.45a

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.10.45a

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

ave ts05 firmware MITIGATE

Affected: 1.10.36

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.10.36

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

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-2020-21991?

dominaplus: upgrade to newer than 1.10.77; 53ab-wbs firmware: mitigate or apply the listed mitigation; ts01 firmware: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2020-21991 being exploited?

CVE-2020-21991 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-2020-21991 affect?

CVE-2020-21991 affects dominaplus, 53ab-wbs firmware, ts01 firmware. Severity is critical (CVSS 9.8). AVE DOMINAplus <=1.10.x suffers from an authentication bypass vulnerability due to missing control check when directly calling the autologin GET parameter in changeparams.php script. Setting the autologin value to 1 allows an unauthenticate

How urgent is CVE-2020-21991?

Priority 66/100. Critical severity; Public exploit reference; Remotely exploitable, no login, no user action

Software pages

PHP vulnerabilities

Related CVEs

CVE-2020-21996 HIGH 7.5 UPGRADE MITIGATE AVE DOMINAplus <=1.10.x suffers from an unauthenticated reboot command execution
CVE-2020-21994 CRITICAL 9.8 UPGRADE MITIGATE AVE DOMINAplus <=1.10.x suffers from clear-text credentials disclosure vulnerability that allows an unauthenti

References

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