CVE-2024-20509

mediumpriority · track · 24EPSS 0.004 · 33 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.39% (33rd) EPSS

CVSS 5.9 · medium

Is it mine?

38 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cisco_csaf · nvd

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 hijack an AnyConnect VPN session or cause a denial of service (DoS) condition for individual users of the AnyConnect VPN service on an affected device. This vulnerability is due to weak entropy for handlers that are used during the VPN authentication process as well as a race condition that exists in the same process. An attacker could exploit this vulnerability by correctly guessing an authentication handler and then sending crafted HTTPS requests to an affected device. A successful exploit could allow the attacker to take over the AnyConnect VPN session from a target user or prevent the target user from establishing an AnyConnect VPN session with the affected device.

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.

5.9

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.2 · impact 3.6

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

v3.15.4mediumCVSS:3.1/AV:N/AC:H/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.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-362USprimary

affected products (38)

Products and version ranges known to be affected.

Cisco Cisco Meraki MX Firmwareall versionscisco_csafUS
Cisco Cisco Meraki MX Firmware≤ -9enisa_euvdEU
Cisco Cisco Meraki MX Firmware≤ .16.6enisa_euvdEU
Cisco Cisco Meraki MX Firmware≤ -8enisa_euvdEU
Cisco Cisco Meraki MX Firmware≤ -16-3enisa_euvdEU
Cisco Cisco Meraki MX Firmware≤ -16-2enisa_euvdEU
Cisco Cisco Meraki MX Firmware≤ -6enisa_euvdEU
Cisco Cisco Meraki MX Firmware≤ -10enisa_euvdEU
Cisco Cisco Meraki MX Firmware≤ -16-4enisa_euvdEU
Cisco Cisco Meraki MX Firmware≤ -3enisa_euvdEU
Cisco Cisco Meraki MX Firmware≤ -7enisa_euvdEU
Cisco Cisco Meraki MX Firmware≤ N/Aenisa_euvdEU
Cisco Cisco Meraki MX Firmware≤ -16-5enisa_euvdEU
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 (1)

Vendor and ecosystem advisories describing this.

cisco-sa-meraki-mx-vpn-dos-by-QWUkqV7XCisco Meraki MX and Z Series Teleworker Gateway AnyConnect VPN Session Takeover and Denial of Service Vulnerability2024-10-02csaf · cisco_csafUS
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 hijack an AnyConnect VPN session or cause a denial of service (DoS) condition for individual users of the AnyConnect VPN service on an affected device. This vulnerability is due to weak entropy for handlers that are used during the VPN authentication process as well as a race condition that exists in the same process. An attacker could exploit this vulnerability by correctly guessing an authentication handler and then sending crafted HTTPS requests to an affected device. A successful exploit could allow the attacker to take over the AnyConnect VPN session from a target user or prevent the target user from establishing an AnyConnect VPN session with the affected device. Cisco Meraki has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd 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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