CVE-2023-20155Network attack vector

Unauthenticated appliance disruption via unthrottled log requests

Published Nov 1, 2023 · Updated Aug 2, 2024

Uncontrolled resource consumption in Cisco Firepower Management Center allows remote attackers to hang or reload the appliance via HTTP requests. The FMC log API does not rate-limit requests, so a high request rate drives CPU utilization to 100 percent and can trigger a reload. The API is exposed in the default configuration; remote authenticated users without Administrator privileges can also read a normally restricted system log.

CVSS severity7.5
High
EPSS probability0.67%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled resource consumption in Cisco Firepower Management Center allows remote attackers to hang or reload the appliance via HTTP requests. The FMC log API does not rate-limit requests, so a high request rate drives CPU utilization to 100 percent and can trigger a reload. The API is exposed in the default configuration; remote authenticated users without Administrator privileges can also read a normally restricted system log.

The record

CVE
CVE-2023-20155
Published
Nov 1, 2023
Updated
Aug 2, 2024
Vendor
ClamAV
Product
Cisco Firepower Management Center
Classifications
CWE-770, CWE-400, T1499.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 1, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 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=6.2.3
  2. Affected versionversion=6.2.3.1
  3. Affected versionversion=6.2.3.10
  4. Affected versionversion=6.2.3.11
  5. Affected versionversion=6.2.3.12
  6. Affected versionversion=6.2.3.13
  7. Affected versionversion=6.2.3.14
  8. Affected versionversion=6.2.3.15
  9. Affected versionversion=6.2.3.16
  10. Affected versionversion=6.2.3.17
  11. Affected versionversion=6.2.3.18
  12. Affected versionversion=6.2.3.2
  13. Affected versionversion=6.2.3.3
  14. Affected versionversion=6.2.3.4
  15. Affected versionversion=6.2.3.5
  16. Affected versionversion=6.2.3.6
  17. Affected versionversion=6.2.3.7
  18. Affected versionversion=6.2.3.8
  19. Affected versionversion=6.2.3.9
  20. Affected versionversion=6.4.0
  21. Affected versionversion=6.4.0.1
  22. Affected versionversion=6.4.0.10
  23. Affected versionversion=6.4.0.11
  24. Affected versionversion=6.4.0.12
  25. Affected versionversion=6.4.0.13
  26. Affected versionversion=6.4.0.14
  27. Affected versionversion=6.4.0.15
  28. Affected versionversion=6.4.0.16
  29. Affected versionversion=6.4.0.2
  30. Affected versionversion=6.4.0.3
  31. Affected versionversion=6.4.0.4
  32. Affected versionversion=6.4.0.5
  33. Affected versionversion=6.4.0.6
  34. Affected versionversion=6.4.0.7
  35. Affected versionversion=6.4.0.8
  36. Affected versionversion=6.4.0.9
  37. Affected versionversion=6.6.0
  38. Affected versionversion=6.6.0.1
  39. Affected versionversion=6.6.1
  40. Affected versionversion=6.6.3
  41. Affected versionversion=6.6.4
  42. Affected versionversion=6.6.5
  43. Affected versionversion=6.6.5.1
  44. Affected versionversion=6.6.5.2
  45. Affected versionversion=6.6.7
  46. Affected versionversion=6.6.7.1
  47. Affected versionversion=6.7.0
  48. Affected versionversion=6.7.0.1
  49. Affected versionversion=6.7.0.2
  50. Affected versionversion=6.7.0.3
  51. Affected versionversion=7.0.0
  52. Affected versionversion=7.0.0.1
  53. Affected versionversion=7.0.1
  54. Affected versionversion=7.0.1.1
  55. Affected versionversion=7.0.2
  56. Affected versionversion=7.0.2.1
  57. Affected versionversion=7.0.3
  58. Affected versionversion=7.0.4
  59. Affected versionversion=7.0.5
  60. Affected versionversion=7.1.0
  61. Affected versionversion=7.1.0.1
  62. Affected versionversion=7.1.0.2
  63. Affected versionversion=7.1.0.3
  64. Affected versionversion=7.2.0
  65. Affected versionversion=7.2.0.1
  66. Affected versionversion=7.2.1
  67. Affected versionversion=7.2.2
  68. Affected versionversion=7.2.3
  69. Affected versionversion=7.2.3.1
  70. Affected versionversion=7.3.0
  71. Affected versionversion=7.3.1
  72. Affected versionversion=7.3.1.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco Firepower Management Centerversion=6.2.3; version=6.2.3.1; version=6.2.3.10; version=6.2.3.11; version=6.2.3.12; version=6.2.3.13; version=6.2.3.14; version=6.2.3.15; version=6.2.3.16; version=6.2.3.17; version=6.2.3.18; version=6.2.3.2; version=6.2.3.3; version=6.2.3.4; version=6.2.3.5; version=6.2.3.6; version=6.2.3.7; version=6.2.3.8; version=6.2.3.9; version=6.4.0; version=6.4.0.1; 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=6.4.0.2; version=6.4.0.3; version=6.4.0.4; version=6.4.0.5; version=6.4.0.6; version=6.4.0.7; 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=6.7.0; 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=7.1.0; version=7.1.0.1; version=7.1.0.2; version=7.1.0.3; version=7.2.0; version=7.2.0.1; version=7.2.1; version=7.2.2; version=7.2.3; version=7.2.3.1; version=7.3.0; version=7.3.1; version=7.3.1.1

Published CVSS scores

6.5NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
7.5Cisco Systems, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
CWE-400Uncontrolled Resource Consumption
T1499.003Application Exhaustion Flood

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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