CVE-2019-18840
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.97%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 1.97% probability · 79th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-787
- Affected
- wolfssl/wolfssl
- Source
- cve@mitre.org
References
- https://github.com/wolfSSL/wolfssl/issues/2555Exploit, Third Party Advisory
- https://github.com/wolfSSL/wolfssl/issues/2555Exploit, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.