CVE-2024-20500

highpriority · track · 30EPSS 0.006 · 46 %ileDEEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.55% (46th) EPSS

CVSS 7.5 · high

Is it mine?

38 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

A vulnerability in the Cisco AnyConnect VPN server of Cisco Meraki MX and Cisco Meraki Z Series Teleworker Gateway devices could allow an unauthenticated, remote attacker to cause a DoS condition in the AnyConnect service on an affected device. This vulnerability is due to insufficient resource management when establishing TLS/SSL sessions. An attacker could exploit this vulnerability by sending a series of crafted TLS/SSL messages to the VPN server of an affected device. A successful exploit could allow the attacker to cause the Cisco AnyConnect VPN server to stop accepting new connections, preventing new SSL VPN connections from being established. Existing SSL VPN sessions are not impacted. Note: When the attack traffic stops, the Cisco AnyConnect VPN server recovers gracefully without requiring manual intervention.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

FixedCisco Meraki MX Firmwarecisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.8–7.5

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.15.8mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Lsecondary · ENISA EU

v3.15.8mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Lsecondary · psirt@cisco.com USexploitability 3.9 · impact 1.4

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

v3.15.8mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Lsecondary · Cisco PSIRT US

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USprimaryCWE-400US

affected products (38)

Products and version ranges known to be affected.

Cisco Meraki MX 16.2all versionscert_bundDEcpe:/h:cisco:meraki_mx:16.2
Cisco Meraki MX 17all versionscert_bundDEcpe:/h:cisco:meraki_mx:17
Cisco Meraki MX <18.107.12all versionscert_bundDE
Cisco Meraki MX <18.211.2all versionscert_bundDE
Cisco Meraki MX< 18.107.12cert_bundDE
Cisco Meraki MX< 18.211.2cert_bundDE
Cisco Cisco Meraki MX Firmwareall versionscisco_csafUS
Cisco Cisco Meraki MX Firmware≤ N/Aenisa_euvdEU
Cisco Systems Inc. Cisco Meraki MX≤ 18.107.12fstec_bduRU
Cisco Systems Inc. Cisco Meraki MX≤ 17fstec_bduRU
Cisco Systems Inc. Cisco Meraki MX≤ 18.211.2fstec_bduRU
Cisco Systems Inc. Cisco Meraki MX≤ 16.2fstec_bduRU
Cisco Systems Inc. Cisco Meraki Z Series Teleworker Gatewayall versionsfstec_bduRU
cisco meraki mx100 firmware16.2 → 18.211.2nvdUScpe:2.3:o:cisco:meraki_mx100_firmware:*:*:*:*:*:*:*:*
cisco meraki mx105 firmware16.2 → 18.211.2nvdUScpe:2.3:o:cisco:meraki_mx105_firmware:*:*:*:*:*:*:*:*
cisco meraki mx250 firmware16.2 → 18.211.2nvdUScpe:2.3:o:cisco:meraki_mx250_firmware:*:*:*:*:*:*:*:*
cisco meraki mx400 firmware16.2 → 18.211.2nvdUScpe:2.3:o:cisco:meraki_mx400_firmware:*:*:*:*:*:*:*:*
cisco meraki mx450 firmware16.2 → 18.211.2nvdUScpe:2.3:o:cisco:meraki_mx450_firmware:*:*:*:*:*:*:*:*
cisco meraki mx600 firmware16.2 → 18.211.2nvdUScpe:2.3:o:cisco:meraki_mx600_firmware:*:*:*:*:*:*:*:*
cisco meraki mx64 firmware17.6.0 → 18.211.2nvdUScpe:2.3:o:cisco:meraki_mx64_firmware:*:*:*:*:*:*:*:*

showing 20 of 38

advisories (2)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2025-1214Cisco Meraki MX: Mehrere Schwachstellen ermöglichen Denial of ServiceDeutsch2025-06-02csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Cisco Meraki MX ausnutzen, um einen Denial of Service Angriff durchzuführen.
cisco-sa-meraki-mx-vpn-dos-QTRHzG2Cisco Meraki MX and Z Series Teleworker Gateway AnyConnect VPN Denial of Service Vulnerabilities2024-10-02csaf · cisco_csafUS
Multiple vulnerabilities in the Cisco AnyConnect VPN server of Cisco Meraki MX and Cisco Meraki Z Series Teleworker Gateway devices could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition to the AnyConnect VPN service on an affected device. For more information about these vulnerabilities, see the Details ["#details"] section of this advisory. Cisco Meraki has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund cisco_csaf nvd NVD CVE.org MITRE

published 2024-10-02modified 2026-06-17

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references (6)

External citations — patches, advisories, analysis.

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