How severe is CVE-2019-16748?

CVE-2019-16748 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2019-16748 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-16748?

CVE-2019-16748 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-16748?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2019-16748 published?

CVE-2019-16748 was published on 2019-09-24 and last updated on 2026-06-17.

CVE-2019-16748

CVE-2019-16748 is a critical-severity vulnerability in Wolfssl with a CVSS 3.x base score of 9.8. 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-125.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Wolfssl
Published: 2019-09-24
Last modified: 2026-06-17

Description

In wolfSSL through 4.1.0, there is a missing sanity check of memory accesses in parsing ASN.1 certificate data while handshaking. Specifically, there is a one-byte heap-based buffer over-read in CheckCertSignature_ex in wolfcrypt/src/asn.c.

Frequently asked questions

What is CVE-2019-16748?: In wolfSSL through 4.1.0, there is a missing sanity check of memory accesses in parsing ASN.1 certificate data while handshaking. Specifically, there is a one-byte heap-based buffer over-read in CheckCertSignature_ex in wolfcrypt/src/asn.c.
How severe is CVE-2019-16748?: CVE-2019-16748 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2019-16748 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-16748?: CVE-2019-16748 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-16748?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2019-16748 published?: CVE-2019-16748 was published on 2019-09-24 and last updated on 2026-06-17.

References

https://github.com/wolfSSL/wolfssl/issues/2459

Affected products (1)

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

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