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Out-of-Bound Write in tcp_flags

High
ceolin published GHSA-5c3j-p8cr-2pgh Aug 25, 2022

Package

zephyr (west)

Affected versions

<= v3.0

Patched versions

<= 3.0

Description

Impact

In subsys/net/ip/tcp.c , function tcp_flags , when the incoming parameter flags is ECN
or CWR , the buf will out-of-bounds write a byte zero.

When a malformed tcp packet is received, the tcp_flags function does not check the
validity of the parameters, but directly parses the th_flags field in TCP header. When
th_flags is ECN or CWR , in the tcp_flags function, len is always 0, and buf[0-1] will be
written '\0' . This will modify other data on the stack.

Patches

For more information

If you have any questions or comments about this advisory:

embargo: 2022-08-18

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Changed
Confidentiality
None
Integrity
Low
Availability
Low

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:L

CVE ID

CVE-2022-1841

Weaknesses