CVE-2024-20495Network attack vector

Device reload via malformed TLS client key

Published Oct 23, 2024 · Updated Oct 23, 2024

Improper input validation in Cisco ASA and FTD Remote Access VPN allows remote attackers to trigger unexpected device reloads over TLS. After a TLS session is established, the feature accepts a crafted client key value without adequate validation and processes it until the device reloads. Exposure requires a vulnerable ASA or FTD release with Remote Access VPN enabled; successful exploitation interrupts firewall and VPN service.

CVSS severity8.6
High
EPSS probability0.51%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Cisco ASA and FTD Remote Access VPN allows remote attackers to trigger unexpected device reloads over TLS. After a TLS session is established, the feature accepts a crafted client key value without adequate validation and processes it until the device reloads. Exposure requires a vulnerable ASA or FTD release with Remote Access VPN enabled; successful exploitation interrupts firewall and VPN service.

The record

CVE
CVE-2024-20495
Published
Oct 23, 2024
Updated
Oct 23, 2024
Vendor
ClamAV
Product
Cisco Adaptive Security Appliance (ASA) Software
Classifications
CWE-20, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 23, 2024CVE publishedPublication date reported by the CVE source.
  2. Oct 23, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=9.12.3
  2. Affected versionversion=9.12.3.12
  3. Affected versionversion=9.12.3.2
  4. Affected versionversion=9.12.3.7
  5. Affected versionversion=9.12.3.9
  6. Affected versionversion=9.12.4
  7. Affected versionversion=9.12.4.10
  8. Affected versionversion=9.12.4.13
  9. Affected versionversion=9.12.4.18
  10. Affected versionversion=9.12.4.2
  11. Affected versionversion=9.12.4.24
  12. Affected versionversion=9.12.4.26
  13. Affected versionversion=9.12.4.29
  14. Affected versionversion=9.12.4.30
  15. Affected versionversion=9.12.4.35
  16. Affected versionversion=9.12.4.37
  17. Affected versionversion=9.12.4.38
  18. Affected versionversion=9.12.4.39
  19. Affected versionversion=9.12.4.4
  20. Affected versionversion=9.12.4.40
  21. Affected versionversion=9.12.4.41
  22. Affected versionversion=9.12.4.47
  23. Affected versionversion=9.12.4.48
  24. Affected versionversion=9.12.4.50
  25. Affected versionversion=9.12.4.52
  26. Affected versionversion=9.12.4.54
  27. Affected versionversion=9.12.4.55
  28. Affected versionversion=9.12.4.56
  29. Affected versionversion=9.12.4.58
  30. Affected versionversion=9.12.4.62
  31. Affected versionversion=9.12.4.65
  32. Affected versionversion=9.12.4.67
  33. Affected versionversion=9.12.4.7
  34. Affected versionversion=9.12.4.8
  35. Affected versionversion=9.14.1
  36. Affected versionversion=9.14.1.10
  37. Affected versionversion=9.14.1.15
  38. Affected versionversion=9.14.1.19
  39. Affected versionversion=9.14.1.30
  40. Affected versionversion=9.14.1.6
  41. Affected versionversion=9.14.2
  42. Affected versionversion=9.14.2.13
  43. Affected versionversion=9.14.2.15
  44. Affected versionversion=9.14.2.4
  45. Affected versionversion=9.14.2.8
  46. Affected versionversion=9.14.3
  47. Affected versionversion=9.14.3.1
  48. Affected versionversion=9.14.3.11
  49. Affected versionversion=9.14.3.13
  50. Affected versionversion=9.14.3.15
  51. Affected versionversion=9.14.3.18
  52. Affected versionversion=9.14.3.9
  53. Affected versionversion=9.14.4
  54. Affected versionversion=9.14.4.12
  55. Affected versionversion=9.14.4.13
  56. Affected versionversion=9.14.4.14
  57. Affected versionversion=9.14.4.15
  58. Affected versionversion=9.14.4.17
  59. Affected versionversion=9.14.4.22
  60. Affected versionversion=9.14.4.23
  61. Affected versionversion=9.14.4.24
  62. Affected versionversion=9.14.4.6
  63. Affected versionversion=9.14.4.7
  64. Affected versionversion=9.15.1
  65. Affected versionversion=9.15.1.1
  66. Affected versionversion=9.15.1.10
  67. Affected versionversion=9.15.1.15
  68. Affected versionversion=9.15.1.16
  69. Affected versionversion=9.15.1.17
  70. Affected versionversion=9.15.1.21
  71. Affected versionversion=9.15.1.7
  72. Affected versionversion=9.16.1
  73. Affected versionversion=9.16.1.28
  74. Affected versionversion=9.16.2
  75. Affected versionversion=9.16.2.11
  76. Affected versionversion=9.16.2.13
  77. Affected versionversion=9.16.2.14
  78. Affected versionversion=9.16.2.3
  79. Affected versionversion=9.16.2.7
  80. Affected versionversion=9.16.3
  81. Affected versionversion=9.16.3.14
  82. Affected versionversion=9.16.3.15
  83. Affected versionversion=9.16.3.19
  84. Affected versionversion=9.16.3.23
  85. Affected versionversion=9.16.3.3
  86. Affected versionversion=9.16.4
  87. Affected versionversion=9.16.4.14
  88. Affected versionversion=9.16.4.18
  89. Affected versionversion=9.16.4.19
  90. Affected versionversion=9.16.4.27
  91. Affected versionversion=9.16.4.38
  92. Affected versionversion=9.16.4.39
  93. Affected versionversion=9.16.4.42
  94. Affected versionversion=9.16.4.48
  95. Affected versionversion=9.16.4.55
  96. Affected versionversion=9.16.4.57
  97. Affected versionversion=9.16.4.61
  98. Affected versionversion=9.16.4.62
  99. Affected versionversion=9.16.4.9
  100. Affected versionversion=9.17.1
  101. Affected versionversion=9.17.1.10
  102. Affected versionversion=9.17.1.11
  103. Affected versionversion=9.17.1.13
  104. Affected versionversion=9.17.1.15
  105. Affected versionversion=9.17.1.20
  106. Affected versionversion=9.17.1.30
  107. Affected versionversion=9.17.1.33
  108. Affected versionversion=9.17.1.39
  109. Affected versionversion=9.17.1.7
  110. Affected versionversion=9.17.1.9
  111. Affected versionversion=9.8.4.12
  112. Affected versionversion=9.8.4.15
  113. Affected versionversion=9.8.4.17
  114. Affected versionversion=9.8.4.20
  115. Affected versionversion=9.8.4.22
  116. Affected versionversion=9.8.4.25
  117. Affected versionversion=9.8.4.26
  118. Affected versionversion=9.8.4.29
  119. Affected versionversion=9.8.4.32
  120. Affected versionversion=9.8.4.33
  121. Affected versionversion=9.8.4.34
  122. Affected versionversion=9.8.4.35
  123. Affected versionversion=9.8.4.39
  124. Affected versionversion=9.8.4.40
  125. Affected versionversion=9.8.4.41
  126. Affected versionversion=9.8.4.43
  127. Affected versionversion=9.8.4.44
  128. Affected versionversion=9.8.4.45
  129. Affected versionversion=9.8.4.46
  130. Affected versionversion=9.8.4.48

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco Adaptive Security Appliance (ASA) Softwareversion=9.12.3; version=9.12.3.12; version=9.12.3.2; version=9.12.3.7; version=9.12.3.9; version=9.12.4; version=9.12.4.10; version=9.12.4.13; version=9.12.4.18; version=9.12.4.2; version=9.12.4.24; version=9.12.4.26; version=9.12.4.29; version=9.12.4.30; version=9.12.4.35; version=9.12.4.37; version=9.12.4.38; version=9.12.4.39; version=9.12.4.4; version=9.12.4.40; version=9.12.4.41; version=9.12.4.47; version=9.12.4.48; version=9.12.4.50; version=9.12.4.52; version=9.12.4.54; version=9.12.4.55; version=9.12.4.56; version=9.12.4.58; version=9.12.4.62; version=9.12.4.65; version=9.12.4.67; version=9.12.4.7; version=9.12.4.8; version=9.14.1; version=9.14.1.10; version=9.14.1.15; version=9.14.1.19; version=9.14.1.30; version=9.14.1.6; version=9.14.2; version=9.14.2.13; version=9.14.2.15; version=9.14.2.4; version=9.14.2.8; version=9.14.3; version=9.14.3.1; version=9.14.3.11; version=9.14.3.13; version=9.14.3.15; version=9.14.3.18; version=9.14.3.9; version=9.14.4; version=9.14.4.12; version=9.14.4.13; version=9.14.4.14; version=9.14.4.15; version=9.14.4.17; version=9.14.4.22; version=9.14.4.23; version=9.14.4.24; version=9.14.4.6; version=9.14.4.7; version=9.15.1; version=9.15.1.1; version=9.15.1.10; version=9.15.1.15; version=9.15.1.16; version=9.15.1.17; version=9.15.1.21; version=9.15.1.7; version=9.16.1; version=9.16.1.28; version=9.16.2; version=9.16.2.11; version=9.16.2.13; version=9.16.2.14; version=9.16.2.3; version=9.16.2.7; version=9.16.3; version=9.16.3.14; version=9.16.3.15; version=9.16.3.19; version=9.16.3.23; version=9.16.3.3; version=9.16.4; version=9.16.4.14; version=9.16.4.18; version=9.16.4.19; version=9.16.4.27; version=9.16.4.38; version=9.16.4.39; version=9.16.4.42; version=9.16.4.48; version=9.16.4.55; version=9.16.4.57; version=9.16.4.61; version=9.16.4.62; version=9.16.4.9; version=9.17.1; version=9.17.1.10; version=9.17.1.11; version=9.17.1.13; version=9.17.1.15; version=9.17.1.20; version=9.17.1.30; version=9.17.1.33; version=9.17.1.39; version=9.17.1.7; version=9.17.1.9; version=9.8.4.12; version=9.8.4.15; version=9.8.4.17; version=9.8.4.20; version=9.8.4.22; version=9.8.4.25; version=9.8.4.26; version=9.8.4.29; version=9.8.4.32; version=9.8.4.33; version=9.8.4.34; version=9.8.4.35; version=9.8.4.39; version=9.8.4.40; version=9.8.4.41; version=9.8.4.43; version=9.8.4.44; version=9.8.4.45; version=9.8.4.46; version=9.8.4.48
ClamAV · Cisco Firepower Threat Defenseversion=6.2.3.16; version=6.2.3.17; version=6.2.3.18; version=6.4.0.10; version=6.4.0.11; version=6.4.0.12; version=6.4.0.13; version=6.4.0.14; version=6.4.0.15; version=6.4.0.16; version=6.4.0.17; version=6.4.0.18; version=6.4.0.8; version=6.4.0.9; version=6.6.0; version=6.6.0.1; version=6.6.1; version=6.6.3; version=6.6.4; version=6.6.5; version=6.6.5.1; version=6.6.5.2; version=6.6.7; version=6.6.7.1; version=6.6.7.2; version=6.7.0; version=6.7.0.1; version=6.7.0.2; version=6.7.0.3; version=7.0.0; version=7.0.0.1; version=7.0.1; version=7.0.1.1; version=7.0.2; version=7.0.2.1; version=7.0.3; version=7.0.4; version=7.0.5; version=7.0.6; version=7.0.6.1; version=7.0.6.2; version=7.1.0; version=7.1.0.1; version=7.1.0.2; version=7.1.0.3

Published CVSS scores

8.6Cisco Systems, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:X/RL:X/RC:X

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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