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. Specifically, there is…

PriorityP339high7.5CVSS 3.1

AVNACLPRNUINSUCNINAH

EPSS

1.97%

78.2th percentile

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

6 ranges

Vendor	Product	Version range	Fixed in
debian	wolfssl	< wolfssl 4.2.0+dfsg-3 (bookworm)	wolfssl 4.2.0+dfsg-3 (bookworm)
wolfssl	wolfssl	>= 0 < 4.2.0+dfsg-3	4.2.0+dfsg-3
wolfssl	wolfssl	>= 0 < 4.2.0+dfsg-3	4.2.0+dfsg-3
wolfssl	wolfssl	>= 0 < 4.2.0+dfsg-3	4.2.0+dfsg-3
wolfssl	wolfssl	>= 0 < 4.2.0+dfsg-3	4.2.0+dfsg-3
wolfssl	wolfssl	4.1.0 – 4.2.0c	—

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvdv3.07.5HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P

osv7.5HIGH

vendor_debian7.5HIGH

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