CVE-2019-17185: In FreeRADIUS 3.0.x before 3.0.20, the EAP-pwd module used a global OpenSSL BN_CTX instance to handle all hand

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HIGH 7.5REMOTEWATCHLISTUPGRADEMITIGATE

CVE-2019-17185 is a high-severity flaw (CVSS 7.5) affecting freeradius, leap. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

In FreeRADIUS 3.0.x before 3.0.20, the EAP-pwd module used a global OpenSSL BN_CTX instance to handle all handshakes. This mean multiple threads use the same BN_CTX instance concurrently, resulting in crashes when concurrent EAP-pwd handshakes are initiated. This can be abused by an adversary as a Denial-of-Service (DoS) attack.

Why this priority

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

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	2.2% (top 17%)
CISA exploited list	No
Weakness	CWE-662
Published	2020-03-21
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: freeradius · opensuse

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

Am I affected?

Timeline

2020-03-21 01:15 UTCPublished CVE record published
2026-06-17 02:23 UTCUpdated Record last modified

freeradius freeradius UPGRADE

Affected: >= 3.0.0 and < 3.0.20

Fixed in: 3.0.20

Safe to downgrade to: a release before 3.0.0

1. Check installed version

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

2. UPGRADE to 3.0.20 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade freeradius

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 3.0.0 (Debian / Ubuntu)

apt-cache madison freeradius sudo apt install freeradius=<VERSION_BEFORE_3.0.0> sudo apt-mark hold freeradius

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

dnf --showduplicates list freeradius sudo dnf downgrade freeradius-<VERSION_BEFORE_3.0.0> sudo dnf versionlock add freeradius

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.

opensuse leap MITIGATE

Affected: 15.1

Fixed in: no fixed release known

Safe to downgrade to: a release before 15.1

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-2019-17185?

freeradius: upgrade to 3.0.20; leap: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2019-17185 being exploited?

CVE-2019-17185 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-2019-17185 affect?

CVE-2019-17185 affects freeradius, leap. Severity is high (CVSS 7.5). In FreeRADIUS 3.0.x before 3.0.20, the EAP-pwd module used a global OpenSSL BN_CTX instance to handle all handshakes. This mean multiple threads use the same BN_CTX instance concurrently, resulting in crashes when concurrent EAP-pwd handsha

How urgent is CVE-2019-17185?

Priority 57/100. High severity; Remotely exploitable, no login, no user action; On your watchlist

Software pages

OpenSSL vulnerabilities

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References

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