How severe is CVE-2020-24613?

CVE-2020-24613 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2020-24613 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-24613?

CVE-2020-24613 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-24613?

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

When was CVE-2020-24613 published?

CVE-2020-24613 was published on 2020-08-24 and last updated on 2026-06-17.

CVE-2020-24613

CVE-2020-24613 is a medium-severity vulnerability in Wolfssl with a CVSS 3.x base score of 6.8. 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-295.

Key facts

Severity: Medium (CVSS 3.x base score 6.8)
CVSS v2: 4.9
EPSS exploit prediction: 1% (54th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Wolfssl
Published: 2020-08-24
Last modified: 2026-06-17

Description

wolfSSL before 4.5.0 mishandles TLS 1.3 server data in the WAIT_CERT_CR state, within SanityCheckTls13MsgReceived() in tls13.c. This is an incorrect implementation of the TLS 1.3 client state machine. This allows attackers in a privileged network position to completely impersonate any TLS 1.3 servers, and read or modify potentially sensitive information between clients using the wolfSSL library and these TLS servers.

Frequently asked questions

What is CVE-2020-24613?: wolfSSL before 4.5.0 mishandles TLS 1.3 server data in the WAIT_CERT_CR state, within SanityCheckTls13MsgReceived() in tls13.c. This is an incorrect implementation of the TLS 1.3 client state machine. This allows attackers in a privileged network position to completely impersonate any TLS 1.3 servers, and read or modify potentially sensitive information between clients using the wolfSSL library and these TLS servers.
How severe is CVE-2020-24613?: CVE-2020-24613 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2020-24613 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-24613?: CVE-2020-24613 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-24613?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-24613 published?: CVE-2020-24613 was published on 2020-08-24 and last updated on 2026-06-17.

References

https://research.nccgroup.com/2020/08/24/technical-advisory-wolfssl-tls-1-3-client-man-in-the-middle-attack/

Affected products (1)

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

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