CVE-2020-17439

Severity CVSS v4.0:

Pending analysis

Type:

CWE-20 Input Validation

Publication date:

11/12/2020

Last modified:

15/12/2020

Description

An issue was discovered in uIP 1.0, as used in Contiki 3.0 and other products. The code that parses incoming DNS packets does not validate that the incoming DNS replies match outgoing DNS queries in newdata() in resolv.c. Also, arbitrary DNS replies are parsed if there was any outgoing DNS query with a transaction ID that matches the transaction ID of an incoming reply. Provided that the default DNS cache is quite small (only four records) and that the transaction ID has a very limited set of values that is quite easy to guess, this can lead to DNS cache poisoning.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L CVSS v3.1 Severity and Metrics:

Base Score: 8.30 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Changed
Confidentiality (C): Low
Integrity (I): Low
Availability (A): Low

Base Score 3.x

8.30

Severity 3.x

HIGH

Vector 2.0

AV:N/AC:L/Au:N/C:P/I:P/A:P CVSS v2.0 Severity and Metrics:

Base Score: 7.50 HIGH
Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P

Attack Vector (AV): Network
Attack Complexity (AC): Low
Authentication (Au): None
Confidentiality (C): Physical
Integrity (I): Physical
Availability (A): Physical