CVE-2011-4574: PolarSSL versions prior to v1.1 use the HAVEGE random number generation algorithm

Q: How do I fix CVE-2011-4574?

polarssl: upgrade to 1.1.0. Exact commands for each OS are on this page.

Q: Is CVE-2011-4574 being exploited?

CVE-2011-4574 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2011-4574 affect?

CVE-2011-4574 affects polarssl. Severity is critical (CVSS 9.8). PolarSSL versions prior to v1.1 use the HAVEGE random number generation algorithm. At its heart, this uses timing information based on the processor's high resolution timer (the RDTSC instruction). This instruction can be virtualized, and s

Q: How urgent is CVE-2011-4574?

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

This month

CRITICAL 9.8REMOTEUPGRADE

CVE-2011-4574 is a critical-severity flaw (CVSS 9.8) affecting polarssl. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

PolarSSL versions prior to v1.1 use the HAVEGE random number generation algorithm. At its heart, this uses timing information based on the processor's high resolution timer (the RDTSC instruction). This instruction can be virtualized, and some virtual machine hosts have chosen to disable this instruction, returning 0s or predictable results.

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	1.1% (top 35%)
CISA exploited list	No
Weakness	CWE-338
Published	2021-10-27
Last modified	2026-06-16

Publisher (CNA): Red Hat, Inc. · Vendor: polarssl

Last updated 2026-06-16 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2021-10-27 01:15 UTCPublished CVE record published
2026-06-16 23:35 UTCUpdated Record last modified

polarssl polarssl UPGRADE

Affected: < 1.1.0

Fixed in: 1.1.0

Safe to downgrade to: no unaffected older release

1. Check installed version

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

2. UPGRADE to 1.1.0 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade polarssl

Note

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

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-2011-4574?

polarssl: upgrade to 1.1.0. Exact commands for each OS are on this page.

Is CVE-2011-4574 being exploited?

CVE-2011-4574 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-2011-4574 affect?

CVE-2011-4574 affects polarssl. Severity is critical (CVSS 9.8). PolarSSL versions prior to v1.1 use the HAVEGE random number generation algorithm. At its heart, this uses timing information based on the processor's high resolution timer (the RDTSC instruction). This instruction can be virtualized, and s

How urgent is CVE-2011-4574?

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

References

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