How severe is CVE-2021-24116?

CVE-2021-24116 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-24116 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-24116?

CVE-2021-24116 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-24116?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-24116 published?

CVE-2021-24116 was published on 2021-07-14 and last updated on 2026-06-17.

CVE-2021-24116

CVE-2021-24116 is a medium-severity vulnerability in Wolfssl with a CVSS 3.x base score of 4.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-203.

Key facts

Severity: Medium (CVSS 3.x base score 4.9)
CVSS v2: 4.0
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Wolfssl
Published: 2021-07-14
Last modified: 2026-06-17

Description

In wolfSSL through 4.6.0, a side-channel vulnerability in base64 PEM file decoding allows system-level (administrator) attackers to obtain information about secret RSA keys via a controlled-channel and side-channel attack on software running in isolated environments that can be single stepped, especially Intel SGX.

Frequently asked questions

What is CVE-2021-24116?: In wolfSSL through 4.6.0, a side-channel vulnerability in base64 PEM file decoding allows system-level (administrator) attackers to obtain information about secret RSA keys via a controlled-channel and side-channel attack on software running in isolated environments that can be single stepped, especially Intel SGX.
How severe is CVE-2021-24116?: CVE-2021-24116 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-24116 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-24116?: CVE-2021-24116 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-24116?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-24116 published?: CVE-2021-24116 was published on 2021-07-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*

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