CVE-2023-20240
mediumpriority · track · 22EPSS 0.002 · 9 %ileDEEURUUSEPSS · scored 2026-10-27
Multiple vulnerabilities in Cisco Secure Client Software, formerly AnyConnect Secure Mobility Client, could allow an authenticated, local attacker to cause a denial of service (DoS) condition on an affected system. These vulnerabilities are due to an out-of-bounds memory read from Cisco Secure Client Software. An attacker could exploit these vulnerabilities by logging in to an affected device at the same time that another user is accessing Cisco Secure Client on the same system, and then sending crafted packets to a port on that local host. A successful exploit could allow the attacker to crash the VPN Agent service, causing it to be unavailable to all users of the system. To exploit these vulnerabilities, the attacker must have valid credentials on a multi-user system.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco Secure Clientcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (63)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2023-2931Cisco AnyConnect Secure Mobility Solution: Mehrere Schwachstellen ermöglichen Denial of ServiceDeutsch2023-11-15csaf · cert_bundDE
Ein lokaler Angreifer kann mehrere Schwachstellen in Cisco AnyConnect Secure Mobility Solution ausnutzen, um einen Denial of Service Angriff durchzuführen.
- cisco-sa-accsc-dos-9SLzkZ8Cisco Secure Client Software Denial of Service Vulnerabilities2023-11-15csaf · cisco_csafUS
Multiple vulnerabilities in Cisco Secure Client Software, formerly AnyConnect Secure Mobility Client, could allow an authenticated, local attacker to cause a denial of service (DoS) condition on an affected system. These vulnerabilities are due to an out-of-bounds memory read from Cisco Secure Client Software. An attacker could exploit these vulnerabilities by logging in to an affected device at the same time that another user is accessing Cisco Secure Client on the same system, and then sending crafted packets to a port on that local host. A successful exploit could allow the attacker to crash the VPN Agent service, causing it to be unavailable to all users of the system. To exploit these vulnerabilities, the attacker must have valid credentials on a multi-user system. Cisco has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities. Attention: Simplifying the Cisco portfolio includes the renaming of security products under one brand: Cisco Secure. For more information, see Meet Cisco Secure ["https://www.cisco.com/c/en/us/products/security/secure-names.html"].
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (4)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2023-20240/cnnvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-accsc-dos-9SLzkZ8cnnvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-accsc-dos-9SLzkZ8enisa_euvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-accsc-dos-9SLzkZ8Issue TrackingVendor Advisorynvd
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