CVE-2024-20526

CVE-2024-20526 is a medium-severity vulnerability in Cisco Adaptive Security Appliance Software with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-770.

Key facts

Description

A vulnerability in the SSH server of Cisco Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition for the SSH server of an affected device. This vulnerability is due to a logic error when an SSH session is established. An attacker could exploit this vulnerability by sending crafted SSH messages to an affected device. A successful exploit could allow the attacker to exhaust available SSH resources on the affected device so that new SSH connections to the device are denied, resulting in a DoS condition. Existing SSH connections to the device would continue to function normally. The device must be rebooted manually to recover. However, user traffic would not be impacted and could be managed using a remote application such as Cisco Adaptive Security Device Manager (ASDM).

Frequently asked questions

What is CVE-2024-20526?
A vulnerability in the SSH server of Cisco Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition for the SSH server of an affected device. This vulnerability is due to a logic error when an SSH session is established. An attacker could exploit this vulnerability by sending crafted SSH messages to an affected device. A successful exploit could allow the attacker to exhaust available SSH resources on the affected device so that new SSH connections to the device are denied, resulting in a DoS condition. Existing SSH connections to the device would continue to function normally. The device must be rebooted manually to recover. However, user traffic would not be impacted and could be managed using a remote application such as Cisco Adaptive Security Device Manager (ASDM).
How severe is CVE-2024-20526?
CVE-2024-20526 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2024-20526 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-20526?
CVE-2024-20526 primarily affects Cisco Adaptive Security Appliance Software. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-20526?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-20526 have an EU (EUVD) identifier?
Yes. CVE-2024-20526 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-18241.
When was CVE-2024-20526 published?
CVE-2024-20526 was published on 2024-10-23 and last updated on 2026-06-17.

References

Affected products (4)

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