CVE-2021-34791 - CVE House
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Status published Medium CVE-2021-34791

Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Application Level Gateway Bypass Vulnerabilities

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

Cisco Adaptive Security Appliance (ASA) Software
Vulnerable Versions:
Unknown

Timeline

Official Publish: October 27th, 2021
Last Modified: November 7th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N

Weaknesses (CWE)

CWE-358

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.