CVE-2019-18840: Buffer Overflow
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 Software
Event History
Frequently Asked Questions
What is CVE-2019-18840?
CVE-2019-18840 is a vulnerability in wolfSSL versions 4.1.0 through 4.2.0c that allows for a one-byte heap-based buffer overflow during ASN.1 certificate data parsing.
How severe is CVE-2019-18840?
CVE-2019-18840 has a severity rating of 7.5, indicating a high severity.
Which software versions are affected by CVE-2019-18840?
wolfSSL versions 4.1.0 through 4.2.0c are affected by CVE-2019-18840.
How can I fix CVE-2019-18840?
To fix CVE-2019-18840, users are advised to update to a version of wolfSSL that is higher than 4.2.0c.
Where can I find more information about CVE-2019-18840?
More information about CVE-2019-18840 can be found at the following reference link: [https://github.com/wolfSSL/wolfssl/issues/2555](https://github.com/wolfSSL/wolfssl/issues/2555)