CVE-2021-4213: A flaw was found in JSS, where it did not properly free up all memory

This month

HIGH 7.5REMOTEWATCHLISTUPGRADEMITIGATEMITIGATE

CVE-2021-4213 is a high-severity flaw (CVSS 7.5) affecting network security services for java, enterprise linux, debian linux. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A flaw was found in JSS, where it did not properly free up all memory. Over time, the wasted memory builds up in the server memory, saturating the server’s RAM. This flaw allows an attacker to force the invocation of an out-of-memory process, causing a denial of service.

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	1.7% (top 22%)
CISA exploited list	No
Weakness	CWE-401
Published	2022-08-24
Last modified	2026-06-17

Publisher (CNA): Red Hat, Inc. · Vendor: debian · dogtagpki · redhat

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

Am I affected?

Timeline

2022-08-24 16:15 UTCPublished CVE record published
2026-06-17 04:19 UTCUpdated Record last modified

dogtagpki network security services for java UPGRADE

Affected: < 4.9.3 · >= 5.0.0 and < 5.1.0

Fixed in: 4.9.3, 5.1.0

Safe to downgrade to: a release before 5.0.0

1. Check installed version

apt-cache policy network-security-services-for-java || rpm -q network-security-services-for-java || network-security-services-for-java --version

2. UPGRADE to 4.9.3 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade network-security-services-for-java

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade network-security-services-for-java

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 5.0.0 (Debian / Ubuntu)

apt-cache madison network-security-services-for-java sudo apt install network-security-services-for-java=<VERSION_BEFORE_5.0.0> sudo apt-mark hold network-security-services-for-java

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

dnf --showduplicates list network-security-services-for-java sudo dnf downgrade network-security-services-for-java-<VERSION_BEFORE_5.0.0> sudo dnf versionlock add network-security-services-for-java

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.

redhat enterprise linux MITIGATE

Affected: 8.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 8.0

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.

debian debian linux MITIGATE

Affected: 10.0 · 11.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 10.0

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-2021-4213?

network security services for java: upgrade to 4.9.3, 5.1.0; enterprise linux: mitigate or apply the listed mitigation; debian linux: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2021-4213 being exploited?

CVE-2021-4213 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-2021-4213 affect?

CVE-2021-4213 affects network security services for java, enterprise linux, debian linux. Severity is high (CVSS 7.5). A flaw was found in JSS, where it did not properly free up all memory. Over time, the wasted memory builds up in the server memory, saturating the server’s RAM. This flaw allows an attacker to force the invocation of an out-of-memory proces

How urgent is CVE-2021-4213?

Priority 56/100. High severity; Remotely exploitable, no login, no user action; On your watchlist

Software pages

Java vulnerabilities · Debian vulnerabilities

Related CVEs

CVE-2022-4132 MEDIUM 5.9 UPGRADE MITIGATE A flaw was found in JSS

References

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