CVE-2026-76459Network attack vector

Memory corruption via undisclosed out-of-bounds writes

Published Oct 7, 2026 · Updated Oct 7, 2026

Out-of-bounds writes in Cisco NX-OS Software on affected switches and fabric interconnects allow attackers to corrupt memory. Cisco groups multiple internally discovered flaws under this identifier but does not disclose the affected routines or the inputs that reach the writes. Exposure is independent of device configuration on the listed hardware; the consequences of each underlying write are not individually published.

CVSS severity9.8
Critical
EPSS probability0.31%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds writes in Cisco NX-OS Software on affected switches and fabric interconnects allow attackers to corrupt memory. Cisco groups multiple internally discovered flaws under this identifier but does not disclose the affected routines or the inputs that reach the writes. Exposure is independent of device configuration on the listed hardware; the consequences of each underlying write are not individually published.

The record

CVE
CVE-2026-76459
Published
Oct 7, 2026
Updated
Oct 7, 2026
Vendor
Clam AntiVirus
Product
Cisco Unified Computing System (Managed)
Classifications
CWE-787
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 7, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 7, 2026Record 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=4.0(1a)
  2. Affected versionversion=4.0(1b)
  3. Affected versionversion=4.0(1c)
  4. Affected versionversion=4.0(1d)
  5. Affected versionversion=4.0(2a)
  6. Affected versionversion=4.0(2b)
  7. Affected versionversion=4.0(2d)
  8. Affected versionversion=4.0(2e)
  9. Affected versionversion=4.0(4a)
  10. Affected versionversion=4.0(4b)
  11. Affected versionversion=4.0(4c)
  12. Affected versionversion=4.0(4d)
  13. Affected versionversion=4.0(4e)
  14. Affected versionversion=4.0(4f)
  15. Affected versionversion=4.0(4g)
  16. Affected versionversion=4.0(4h)
  17. Affected versionversion=4.0(4i)
  18. Affected versionversion=4.0(4k)
  19. Affected versionversion=4.0(4l)
  20. Affected versionversion=4.0(4m)
  21. Affected versionversion=4.0(4n)
  22. Affected versionversion=4.0(4o)
  23. Affected versionversion=4.1(1a)
  24. Affected versionversion=4.1(1b)
  25. Affected versionversion=4.1(1c)
  26. Affected versionversion=4.1(1d)
  27. Affected versionversion=4.1(1e)
  28. Affected versionversion=4.1(2a)
  29. Affected versionversion=4.1(2b)
  30. Affected versionversion=4.1(2c)
  31. Affected versionversion=4.1(3a)
  32. Affected versionversion=4.1(3b)
  33. Affected versionversion=4.1(3c)
  34. Affected versionversion=4.1(3d)
  35. Affected versionversion=4.1(3e)
  36. Affected versionversion=4.1(3f)
  37. Affected versionversion=4.1(3h)
  38. Affected versionversion=4.1(3i)
  39. Affected versionversion=4.1(3j)
  40. Affected versionversion=4.1(3k)
  41. Affected versionversion=4.1(3l)
  42. Affected versionversion=4.1(3m)
  43. Affected versionversion=4.1(3n)
  44. Affected versionversion=4.1(4a)
  45. Affected versionversion=4.2(1c)
  46. Affected versionversion=4.2(1d)
  47. Affected versionversion=4.2(1f)
  48. Affected versionversion=4.2(1i)
  49. Affected versionversion=4.2(1k)
  50. Affected versionversion=4.2(1l)
  51. Affected versionversion=4.2(1m)
  52. Affected versionversion=4.2(1n)
  53. Affected versionversion=4.2(2a)
  54. Affected versionversion=4.2(2c)
  55. Affected versionversion=4.2(2d)
  56. Affected versionversion=4.2(2e)
  57. Affected versionversion=4.2(3b)
  58. Affected versionversion=4.2(3d)
  59. Affected versionversion=4.2(3e)
  60. Affected versionversion=4.2(3g)
  61. Affected versionversion=4.2(3h)
  62. Affected versionversion=4.2(3i)
  63. Affected versionversion=4.2(3j)
  64. Affected versionversion=4.2(3k)
  65. Affected versionversion=4.2(3l)
  66. Affected versionversion=4.2(3m)
  67. Affected versionversion=4.2(3n)
  68. Affected versionversion=4.2(3o)
  69. Affected versionversion=4.2(3p)
  70. Affected versionversion=4.2(3r)
  71. Affected versionversion=4.2(3s)
  72. Affected versionversion=4.3(2b)
  73. Affected versionversion=4.3(2c)
  74. Affected versionversion=4.3(2e)
  75. Affected versionversion=4.3(2f)
  76. Affected versionversion=4.3(3a)
  77. Affected versionversion=4.3(3c)
  78. Affected versionversion=4.3(4a)
  79. Affected versionversion=4.3(4b)
  80. Affected versionversion=4.3(4c)
  81. Affected versionversion=4.3(4d)
  82. Affected versionversion=4.3(4e)
  83. Affected versionversion=4.3(4f)
  84. Affected versionversion=4.3(5a)
  85. Affected versionversion=4.3(5c)
  86. Affected versionversion=4.3(5d)
  87. Affected versionversion=4.3(5e)
  88. Affected versionversion=4.3(6a)
  89. Affected versionversion=4.3(6b)
  90. Affected versionversion=4.3(6c)
  91. Affected versionversion=4.3(6d)
  92. Affected versionversion=4.3(6e)
  93. Affected versionversion=4.3(6f)
  94. Affected versionversion=4.3(6g)
  95. Affected versionversion=4.3(6h)
  96. Affected versionversion=4.3(6i)
  97. Affected versionversion=6.0(1b)
  98. Affected versionversion=6.0(1c)
  99. Affected versionversion=6.0(1d)
  100. Affected versionversion=6.0(1e)
  101. Affected versionversion=6.0(1f)
  102. Affected versionversion=6.0(1h)
  103. Affected versionversion=6.0(2b)
  104. Affected versionversion=6.0(2c)
  105. Affected versionversion=6.0(2d)

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Clam AntiVirus · Cisco Unified Computing System (Managed)version=4.0(1a); version=4.0(1b); version=4.0(1c); version=4.0(1d); version=4.0(2a); version=4.0(2b); version=4.0(2d); version=4.0(2e); version=4.0(4a); version=4.0(4b); version=4.0(4c); version=4.0(4d); version=4.0(4e); version=4.0(4f); version=4.0(4g); version=4.0(4h); version=4.0(4i); version=4.0(4k); version=4.0(4l); version=4.0(4m); version=4.0(4n); version=4.0(4o); version=4.1(1a); version=4.1(1b); version=4.1(1c); version=4.1(1d); version=4.1(1e); version=4.1(2a); version=4.1(2b); version=4.1(2c); version=4.1(3a); version=4.1(3b); version=4.1(3c); version=4.1(3d); version=4.1(3e); version=4.1(3f); version=4.1(3h); version=4.1(3i); version=4.1(3j); version=4.1(3k); version=4.1(3l); version=4.1(3m); version=4.1(3n); version=4.1(4a); version=4.2(1c); version=4.2(1d); version=4.2(1f); version=4.2(1i); version=4.2(1k); version=4.2(1l); version=4.2(1m); version=4.2(1n); version=4.2(2a); version=4.2(2c); version=4.2(2d); version=4.2(2e); version=4.2(3b); version=4.2(3d); version=4.2(3e); version=4.2(3g); version=4.2(3h); version=4.2(3i); version=4.2(3j); version=4.2(3k); version=4.2(3l); version=4.2(3m); version=4.2(3n); version=4.2(3o); version=4.2(3p); version=4.2(3r); version=4.2(3s); version=4.3(2b); version=4.3(2c); version=4.3(2e); version=4.3(2f); version=4.3(3a); version=4.3(3c); version=4.3(4a); version=4.3(4b); version=4.3(4c); version=4.3(4d); version=4.3(4e); version=4.3(4f); version=4.3(5a); version=4.3(5c); version=4.3(5d); version=4.3(5e); version=4.3(6a); version=4.3(6b); version=4.3(6c); version=4.3(6d); version=4.3(6e); version=4.3(6f); version=4.3(6g); version=4.3(6h); version=4.3(6i); version=6.0(1b); version=6.0(1c); version=6.0(1d); version=6.0(1e); version=6.0(1f); version=6.0(1h); version=6.0(2b); version=6.0(2c); version=6.0(2d)
Clam AntiVirus · Cisco NX-OS Softwareversion=10.3(1); version=10.3(2); version=10.3(3); version=10.3(3o); version=10.3(3p); version=10.3(3q); version=10.3(3r); version=10.3(3w); version=10.3(3x); version=10.3(4); version=10.3(4a); version=10.3(4g); version=10.3(4h); version=10.3(5); version=10.3(6); version=10.3(7); version=10.3(8); version=10.3(9); version=10.3(99w); version=10.3(99x); version=10.4(1); version=10.4(2); version=10.4(3); version=10.4(4); version=10.4(4g); version=10.4(5); version=10.4(6); version=10.4(7); version=10.5(1); version=10.5(1j); version=10.5(2); version=10.5(3); version=10.5(3e); version=10.5(3o); version=10.5(3p); version=10.5(3s); version=10.5(3t); version=10.5(4); version=10.5(5); version=10.6(1); version=10.6(1s); version=10.6(2); version=10.6(2n); version=10.6(2s); version=10.6(3); version=10.6(3o); version=10.6(3q); version=10.6(3s); version=7.3(0)D1(1); version=7.3(0)DX(1); version=7.3(0)DY(1); version=7.3(1)D1(1); version=7.3(1)DY(1); version=7.3(2)D1(1); version=7.3(2)D1(1d); version=7.3(2)D1(2); version=7.3(2)D1(3); version=7.3(2)D1(3a); version=7.3(3)D1(1); version=7.3(4)D1(1); version=7.3(5)D1(1); version=7.3(6)D1(1); version=7.3(7)D1(1); version=7.3(8)D1(1); version=7.3(9)D1(1); version=8.1(1); version=8.1(1a); version=8.1(1b); version=8.1(2); version=8.1(2a); version=8.2(1); version=8.2(10); version=8.2(11); version=8.2(2); version=8.2(3); version=8.2(4); version=8.2(5); version=8.2(6); version=8.2(7); version=8.2(7a); version=8.2(8); version=8.2(9); version=8.3(1); version=8.3(2); version=8.4(1); version=8.4(10); version=8.4(11); version=8.4(12); version=8.4(13); version=8.4(1a); version=8.4(2); version=8.4(2a); version=8.4(2b); version=8.4(2c); version=8.4(2d); version=8.4(2e); version=8.4(2f); version=8.4(3); version=8.4(4); version=8.4(4a); version=8.4(5); version=8.4(6); version=8.4(6a); version=8.4(7); version=8.4(8); version=8.4(9); version=8.5(1); version=9.2(1); version=9.2(1a); version=9.2(2); version=9.2(2t); version=9.2(2v); version=9.2(3); version=9.2(3y); version=9.2(4); version=9.3(1); version=9.3(10); version=9.3(11); version=9.3(12); version=9.3(13); version=9.3(14); version=9.3(15); version=9.3(16); version=9.3(17); version=9.3(1z); version=9.3(2); version=9.3(2a); version=9.3(3); version=9.3(4); version=9.3(5); version=9.3(5w); version=9.3(6); version=9.3(7); version=9.3(7a); version=9.3(7k); version=9.3(8); version=9.3(9); version=9.4(1); version=9.4(1a); version=9.4(2); version=9.4(2a); version=9.4(3); version=9.4(3a); version=9.4(3b); version=9.4(4); version=9.4(5)
Clam AntiVirus · Cisco NX-OS System Software in ACI Modeversion=15.2(1g); version=15.2(2e); version=15.2(2f); version=15.2(2g); version=15.2(2h); version=15.2(3e); version=15.2(3f); version=15.2(3g); version=15.2(4d); version=15.2(4e); version=15.2(4f); version=15.2(5c); version=15.2(5d); version=15.2(5e); version=15.2(6e); version=15.2(6g); version=15.2(6h); version=15.2(7f); version=15.2(7g); version=15.2(8d); version=15.2(8e); version=15.2(8f); version=15.2(8g); version=15.2(8h); version=15.2(8i); version=15.3(1d); version=15.3(2a); version=15.3(2b); version=15.3(2c); version=15.3(2d); version=15.3(2e); version=15.3(2f); version=16.0(1g); version=16.0(1j); version=16.0(2h); version=16.0(2j); version=16.0(3d); version=16.0(3e); version=16.0(3g); version=16.0(4c); version=16.0(5h); version=16.0(5j); version=16.0(6c); version=16.0(6h); version=16.0(7e); version=16.0(8e); version=16.0(8f); version=16.0(8h); version=16.0(9c); version=16.0(9d); version=16.0(9e); version=16.0(9f); version=16.1(1f); version=16.1(2f); version=16.1(2g); version=16.1(3f); version=16.1(3g); version=16.1(4h); version=16.1(5e); version=16.2(1g); version=16.2(2e)

Published CVSS scores

9.8CiscoCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write

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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