CVE-2021-34791

CVSS V2 Medium 5 CVSS V3 Medium 5.3

Description

Multiple vulnerabilities in the Application Level Gateway (ALG) for the Network Address Translation (NAT) feature of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass the ALG and open unauthorized connections with a host located behind the ALG. For more information about these vulnerabilities, see the Details section of this advisory. Note: These vulnerabilities have been publicly discussed as NAT Slipstreaming.

Overview

CVE ID
CVE-2021-34791

Assigner
ykramarz@cisco.com

Vulnerability Status
Analyzed

Published Version
2021-10-27T19:15:08

Last Modified Date
2022-10-27T16:43:25

Weakness Enumerations

CWE	URL
CWE-20	http://cwe.mitre.org/data/definitions/20.html

CPE Configuration (Product)

CPE	Vulnerable	Operator	Version Start	Version End
		AND
cpe:2.3:a:cisco:adaptive_security_appliance::::::::	1	OR		9.8.4.40
cpe:2.3:a:cisco:adaptive_security_appliance::::::::	1	OR	9.12.0	9.12.4.18
cpe:2.3:a:cisco:adaptive_security_appliance::::::::	1	OR	9.13.0	9.14.2.15
cpe:2.3:a:cisco:adaptive_security_appliance::::::::	1	OR	9.15.0	9.15.1.15
cpe:2.3:a:cisco:firepower_threat_defense::::::::	1	OR		6.4.0.12
cpe:2.3:a:cisco:firepower_threat_defense::::::::	1	OR	6.5.0	6.6.5
cpe:2.3:a:cisco:firepower_threat_defense::::::::	1	OR	6.7.0	6.7.0.2
		AND
cpe:2.3:o:cisco:asa_5512-x_firmware:009.008:::::::*	1	OR
cpe:2.3:o:cisco:asa_5512-x_firmware:009.015:::::::*	1	OR
cpe:2.3:h:cisco:asa_5512-x:-:::::::*	0	OR
		AND
cpe:2.3:o:cisco:asa_5505_firmware:009.008:::::::*	1	OR
cpe:2.3:o:cisco:asa_5505_firmware:009.015:::::::*	1	OR
cpe:2.3:h:cisco:asa_5505:-:::::::*	0	OR
		AND
cpe:2.3:o:cisco:asa_5515-x_firmware:009.008:::::::*	1	OR
cpe:2.3:o:cisco:asa_5515-x_firmware:009.015:::::::*	1	OR
cpe:2.3:h:cisco:asa_5515-x:-:::::::*	0	OR
		AND
cpe:2.3:o:cisco:asa_5525-x_firmware:009.008:::::::*	1	OR
cpe:2.3:o:cisco:asa_5525-x_firmware:009.015:::::::*	1	OR
cpe:2.3:h:cisco:asa_5525-x:-:::::::*	0	OR
		AND
cpe:2.3:o:cisco:asa_5545-x_firmware:009.008:::::::*	1	OR
cpe:2.3:o:cisco:asa_5545-x_firmware:009.015:::::::*	1	OR
cpe:2.3:h:cisco:asa_5545-x:-:::::::*	0	OR
		AND
cpe:2.3:o:cisco:asa_5555-x_firmware:009.008:::::::*	1	OR
cpe:2.3:o:cisco:asa_5555-x_firmware:009.015:::::::*	1	OR
cpe:2.3:h:cisco:asa_5555-x:-:::::::*	0	OR
		AND
cpe:2.3:o:cisco:asa_5580_firmware:009.008:::::::*	1	OR
cpe:2.3:o:cisco:asa_5580_firmware:009.015:::::::*	1	OR
cpe:2.3:h:cisco:asa_5580:-:::::::*	0	OR
		AND
cpe:2.3:o:cisco:asa_5585-x_firmware:009.008:::::::*	1	OR
cpe:2.3:o:cisco:asa_5585-x_firmware:009.015:::::::*	1	OR
cpe:2.3:h:cisco:asa_5585-x:-:::::::*	0	OR

CVSS Version 2

Version
2.0

Vector String
AV:N/AC:L/Au:N/C:N/I:P/A:N

Access Vector
NETWORK

Access Compatibility
LOW

Authentication
NONE

Confidentiality Impact
NONE

Integrity Impact
PARTIAL

Availability Impact
NONE

Base Score
5

Severity
MEDIUM

Exploitability Score
10

Impact Score
2.9

CVSS Version 3

Version
3.1

Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Attack Vector
NETWORK

Attack Compatibility
LOW

Privileges Required
NONE

User Interaction
NONE

Scope
UNCHANGED

Confidentiality Impact
NONE

Availability Impact
NONE

Base Score
5.3

Base Severity
MEDIUM

Exploitability Score
3.9

Impact Score
1.4

References

Reference URL	Reference Tags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-natalg-bypass-cpKGqkng	Vendor Advisory

Sources

Source Name	Source URL
NIST	https://nvd.nist.gov/vuln/detail/CVE-2021-34791
MITRE	https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-34791

History

Created	Old Value	New Value	Data Type	Notes
2022-05-10 06:49:09				Added to TrackCVE
2022-12-05 13:21:55	psirt@cisco.com	ykramarz@cisco.com	CVE Assigner	updated
2022-12-05 13:21:55	2021-10-27T19:15Z	2021-10-27T19:15:08	CVE Published Date	updated
2022-12-05 13:21:55		2022-10-27T16:43:25	CVE Modified Date	updated
2022-12-05 13:21:55		Analyzed	Vulnerability Status	updated