description: An exploitable information leak vulnerability exists in the ustream-ssl library of OpenWrt, versions 18.06.4 and 15.05.1. When connecting to a remote server, the server's SSL certificate is checked but no action is taken when the certificate is invalid. An attacker could exploit this behavior by performing a man-in-the-middle attack, providing any certificate, leading to the theft of all the data sent by the client during the first request.An exploitable information leak vulnerability exists in the ustream-ssl library of OpenWrt, versions 18.06.4 and 15.05.1. When connecting to a remote server, the server's SSL certificate is checked but no action is taken when the certificate is invalid. An attacker could exploit this behavior by performing a man-in-the-middle attack, providing any certificate, leading to the theft of all the data sent by the client during the first request. After an SSL connection is initialized via _ustream_ssl_init, and after any data (e.g. the client's HTTP request) is written to the stream using ustream_printf, the code eventually enters the function _ustream_ssl_poll, which is used to dispatch the read/write events
problem types: CWE-295: Improper Certificate Validation
affected:
{
vendor: OpenWRT
product: OpenWRT
versions:
version: OpenWrt 15.05.1, via wget (busybox), status: affected
version: OpenWrt 18.06.4, via wget (uclient-fetch), status: affected
}
metrics:
cvssV3_1: [
version: 3.1
vectorString: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N
attackVector: NETWORK
attackComplexity: HIGH
privilegesRequired: NONE
userInteraction: NONE
scope: CHANGED
confidentialityImpact: LOW
integrityImpact: NONE
availabilityImpact: NONE
baseScore: 4
baseSeverity: MEDIUM
]