CVE-2020-9449: An insecure random number generation vulnerability in BlaB! AX, BlaB! AX Pro, BlaB! WS (client), and BlaB! WS

This month

HIGH 8.8DOWNGRADEDOWNGRADEDOWNGRADE

CVE-2020-9449 is a high-severity flaw (CVSS 8.8) affecting blab\! ax, blab\! ax pro, blab\! ws. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

An insecure random number generation vulnerability in BlaB! AX, BlaB! AX Pro, BlaB! WS (client), and BlaB! WS Pro (client) version 19.11 allows an attacker (with a guest or user session cookie) to escalate privileges by retrieving the cookie salt value and creating a valid session cookie for an arbitrary user or admin.

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	1.0% (top 36%)
CISA exploited list	No
Weakness	CWE-330
Published	2020-02-28
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: justblab

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

Am I affected?

Timeline

2020-02-28 21:15 UTCPublished CVE record published
2026-06-17 03:27 UTCUpdated Record last modified

justblab blab\! ax DOWNGRADE

Affected: 19.11

Fixed in: no fixed release known

Safe to downgrade to: a release before 19.11

1. Check installed version

apt-cache policy blab-ax || rpm -q blab-ax || blab-ax --version

2. No fixed release: DOWNGRADE to a release before 19.11 (Debian / Ubuntu)

apt-cache madison blab-ax sudo apt install blab-ax=<VERSION_BEFORE_19.11> sudo apt-mark hold blab-ax

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

dnf --showduplicates list blab-ax sudo dnf downgrade blab-ax-<VERSION_BEFORE_19.11> sudo dnf versionlock add blab-ax

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.

justblab blab\! ax pro DOWNGRADE

Affected: 19.11

Fixed in: no fixed release known

Safe to downgrade to: a release before 19.11

1. Check installed version

apt-cache policy blab-ax-pro || rpm -q blab-ax-pro || blab-ax-pro --version

2. No fixed release: DOWNGRADE to a release before 19.11 (Debian / Ubuntu)

apt-cache madison blab-ax-pro sudo apt install blab-ax-pro=<VERSION_BEFORE_19.11> sudo apt-mark hold blab-ax-pro

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

dnf --showduplicates list blab-ax-pro sudo dnf downgrade blab-ax-pro-<VERSION_BEFORE_19.11> sudo dnf versionlock add blab-ax-pro

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.

justblab blab\! ws DOWNGRADE

Affected: 19.11

Fixed in: no fixed release known

Safe to downgrade to: a release before 19.11

1. Check installed version

apt-cache policy blab-ws || rpm -q blab-ws || blab-ws --version

2. No fixed release: DOWNGRADE to a release before 19.11 (Debian / Ubuntu)

apt-cache madison blab-ws sudo apt install blab-ws=<VERSION_BEFORE_19.11> sudo apt-mark hold blab-ws

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

dnf --showduplicates list blab-ws sudo dnf downgrade blab-ws-<VERSION_BEFORE_19.11> sudo dnf versionlock add blab-ws

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.

justblab blab\! ws pro DOWNGRADE

Affected: 19.11

Fixed in: no fixed release known

Safe to downgrade to: a release before 19.11

1. Check installed version

apt-cache policy blab-ws-pro || rpm -q blab-ws-pro || blab-ws-pro --version

2. No fixed release: DOWNGRADE to a release before 19.11 (Debian / Ubuntu)

apt-cache madison blab-ws-pro sudo apt install blab-ws-pro=<VERSION_BEFORE_19.11> sudo apt-mark hold blab-ws-pro

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

dnf --showduplicates list blab-ws-pro sudo dnf downgrade blab-ws-pro-<VERSION_BEFORE_19.11> sudo dnf versionlock add blab-ws-pro

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-2020-9449?

blab\! ax: downgrade or apply the listed mitigation; blab\! ax pro: downgrade or apply the listed mitigation; blab\! ws: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2020-9449 being exploited?

CVE-2020-9449 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-2020-9449 affect?

CVE-2020-9449 affects blab\! ax, blab\! ax pro, blab\! ws. Severity is high (CVSS 8.8). An insecure random number generation vulnerability in BlaB! AX, BlaB! AX Pro, BlaB! WS (client), and BlaB! WS Pro (client) version 19.11 allows an attacker (with a guest or user session cookie) to escalate privileges by retrieving the cooki

How urgent is CVE-2020-9449?

Priority 47/100. High severity

References

← Back to latest CVEs