What’s Vulnerable › Vulnerabilities
CVE-2019-18840
- Severity: high (CVSS 7.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 2.0% probability of exploitation in the next 30 days
- Public exploit or detection template: yes
- Published: 2019-11-09 · updated 2026-06-17
- Weakness: CWE-787
Description
In wolfSSL 4.1.0 through 4.2.0c, there are missing sanity checks of memory accesses in parsing ASN.1 certificate data while handshaking. Specifically, there is a one-byte heap-based buffer overflow inside the DecodedCert structure in GetName in wolfcrypt/src/asn.c because the domain name location index is mishandled. Because a pointer is overwritten, there is an invalid free.
Affected products
- wolfSSL: from 4.1.0 through 4.2.0c
References
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