CWE - CWE-290: Authentication Bypass by Spoofing (4.16)

Weakness ID: 290

Vulnerability Mapping: ALLOWED This CWE ID may be used to map to real-world vulnerabilities
Abstraction: Base Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.

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Description

This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks.

Common Consequences

This table specifies different individual consequences associated with the weakness. The Scope identifies the application security area that is violated, while the Impact describes the negative technical impact that arises if an adversary succeeds in exploiting this weakness. The Likelihood provides information about how likely the specific consequence is expected to be seen relative to the other consequences in the list. For example, there may be high likelihood that a weakness will be exploited to achieve a certain impact, but a low likelihood that it will be exploited to achieve a different impact.

Scope	Impact	Likelihood
Access Control	Technical Impact: Bypass Protection Mechanism; Gain Privileges or Assume Identity This weakness can allow an attacker to access resources which are not otherwise accessible without proper authentication.

Relationships

This table shows the weaknesses and high level categories that are related to this weakness. These relationships are defined as ChildOf, ParentOf, MemberOf and give insight to similar items that may exist at higher and lower levels of abstraction. In addition, relationships such as PeerOf and CanAlsoBe are defined to show similar weaknesses that the user may want to explore.

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	1390	Weak Authentication
ParentOf	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	291	Reliance on IP Address for Authentication
ParentOf	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	293	Using Referer Field for Authentication
ParentOf	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	350	Reliance on Reverse DNS Resolution for a Security-Critical Action
PeerOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	602	Client-Side Enforcement of Server-Side Security

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1211	Authentication Errors

Relevant to the view "Weaknesses for Simplified Mapping of Published Vulnerabilities" (CWE-1003)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	287	Improper Authentication

Relevant to the view "Architectural Concepts" (CWE-1008)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1010	Authenticate Actors

Modes Of Introduction

The different Modes of Introduction provide information about how and when this weakness may be introduced. The Phase identifies a point in the life cycle at which introduction may occur, while the Note provides a typical scenario related to introduction during the given phase.

Phase	Note
Implementation

Demonstrative Examples

Example 1

The following code authenticates users.

(bad code)

Example Language: Java

String sourceIP = request.getRemoteAddr();
if (sourceIP != null && sourceIP.equals(APPROVED_IP)) {

authenticated = true;

}

The authentication mechanism implemented relies on an IP address for source validation. If an attacker is able to spoof the IP, they may be able to bypass the authentication mechanism.

Example 2

Both of these examples check if a request is from a trusted address before responding to the request.

(bad code)

Example Language: C

sd = socket(AF_INET, SOCK_DGRAM, 0);
serv.sin_family = AF_INET;
serv.sin_addr.s_addr = htonl(INADDR_ANY);
servr.sin_port = htons(1008);
bind(sd, (struct sockaddr *) & serv, sizeof(serv));

while (1) {

memset(msg, 0x0, MAX_MSG);
clilen = sizeof(cli);
if (inet_ntoa(cli.sin_addr)==getTrustedAddress()) {

n = recvfrom(sd, msg, MAX_MSG, 0, (struct sockaddr *) & cli, &clilen);

}

(bad code)

Example Language: Java

while(true) {

DatagramPacket rp=new DatagramPacket(rData,rData.length);
outSock.receive(rp);
String in = new String(p.getData(),0, rp.getLength());
InetAddress clientIPAddress = rp.getAddress();
int port = rp.getPort();

if (isTrustedAddress(clientIPAddress) & secretKey.equals(in)) {

out = secret.getBytes();
DatagramPacket sp =new DatagramPacket(out,out.length, IPAddress, port); outSock.send(sp);

}

The code only verifies the address as stored in the request packet. An attacker can spoof this address, thus impersonating a trusted client.

Example 3

The following code samples use a DNS lookup in order to decide whether or not an inbound request is from a trusted host. If an attacker can poison the DNS cache, they can gain trusted status.

(bad code)

Example Language: C

struct hostent *hp;struct in_addr myaddr;
char* tHost = "trustme.example.com";
myaddr.s_addr=inet_addr(ip_addr_string);

hp = gethostbyaddr((char *) &myaddr, sizeof(struct in_addr), AF_INET);
if (hp && !strncmp(hp->h_name, tHost, sizeof(tHost))) {

trusted = true;

} else {

trusted = false;

}

(bad code)

Example Language: Java

String ip = request.getRemoteAddr();
InetAddress addr = InetAddress.getByName(ip);
if (addr.getCanonicalHostName().endsWith("trustme.com")) {

trusted = true;

}

(bad code)

Example Language: C#

IPAddress hostIPAddress = IPAddress.Parse(RemoteIpAddress);
IPHostEntry hostInfo = Dns.GetHostByAddress(hostIPAddress);
if (hostInfo.HostName.EndsWith("trustme.com")) {

trusted = true;

}

IP addresses are more reliable than DNS names, but they can also be spoofed. Attackers can easily forge the source IP address of the packets they send, but response packets will return to the forged IP address. To see the response packets, the attacker has to sniff the traffic between the victim machine and the forged IP address. In order to accomplish the required sniffing, attackers typically attempt to locate themselves on the same subnet as the victim machine. Attackers may be able to circumvent this requirement by using source routing, but source routing is disabled across much of the Internet today. In summary, IP address verification can be a useful part of an authentication scheme, but it should not be the single factor required for authentication.

Observed Examples

Reference	Description
CVE-2022-30319	S-bus functionality in a home automation product performs access control using an IP allowlist, which can be bypassed by a forged IP address.
CVE-2009-1048	VOIP product allows authentication bypass using 127.0.0.1 in the Host header.

Memberships

This MemberOf Relationships table shows additional CWE Categories and Views that reference this weakness as a member. This information is often useful in understanding where a weakness fits within the context of external information sources.

Nature	Type	ID	Name
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	956	SFP Secondary Cluster: Channel Attack
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1353	OWASP Top Ten 2021 Category A07:2021 - Identification and Authentication Failures
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1366	ICS Communications: Frail Security in Protocols
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1396	Comprehensive Categorization: Access Control

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID may be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Carefully read both the name and description to ensure that this mapping is an appropriate fit. Do not try to 'force' a mapping to a lower-level Base/Variant simply to comply with this preferred level of abstraction.

Notes

Relationship

This can be resultant from insufficient verification.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
PLOVER			Authentication bypass by spoofing

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-21	Exploitation of Trusted Identifiers
CAPEC-22	Exploiting Trust in Client
CAPEC-459	Creating a Rogue Certification Authority Certificate
CAPEC-461	Web Services API Signature Forgery Leveraging Hash Function Extension Weakness
CAPEC-473	Signature Spoof
CAPEC-476	Signature Spoofing by Misrepresentation
CAPEC-59	Session Credential Falsification through Prediction
CAPEC-60	Reusing Session IDs (aka Session Replay)
CAPEC-667	Bluetooth Impersonation AttackS (BIAS)
CAPEC-94	Adversary in the Middle (AiTM)

References

[REF-62] Mark Dowd, John McDonald and Justin Schuh. "The Art of Software Security Assessment". Chapter 3, "Spoofing and Identification", Page 72. 1st Edition. Addison Wesley. 2006.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	PLOVER
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Sean Eidemiller	Cigital
2008-07-01	added/updated demonstrative examples
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Description, Relationships, Relationship_Notes, Taxonomy_Mappings
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated Relationship_Notes
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Common_Consequences, Demonstrative_Examples, Observed_Examples, References, Related_Attack_Patterns, Relationships
2013-07-17	CWE Content Team	MITRE
2013-07-17	updated Relationships
2014-02-18	CWE Content Team	MITRE
2014-02-18	updated Related_Attack_Patterns
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Demonstrative_Examples, Relationships
2017-05-03	CWE Content Team	MITRE
2017-05-03	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Demonstrative_Examples, Modes_of_Introduction, Relationships
2019-06-20	CWE Content Team	MITRE
2019-06-20	updated Related_Attack_Patterns, Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2021-07-20	CWE Content Team	MITRE
2021-07-20	updated Related_Attack_Patterns
2021-10-28	CWE Content Team	MITRE
2021-10-28	updated Relationships
2022-10-13	CWE Content Team	MITRE
2022-10-13	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Modes_of_Introduction, Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2023-10-26	CWE Content Team	MITRE
2023-10-26	updated Observed_Examples


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Common Weakness Enumeration

CWE-290: Authentication Bypass by Spoofing

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