CVE-2020-3353Network attack vector

Unauthenticated Application Server crash via syslog race

Published Jun 3, 2020 · Updated Nov 15, 2024

Race condition in the syslog engine of Cisco Identity Services Engine allows remote attackers to crash the Application Server process. Concurrent handling of high-rate syslog messages can trigger improper synchronization in the processing engine and terminate the Application Server. The interface must accept attacker-supplied syslog traffic at high volume; a successful attack interrupts ISE service without reported data disclosure or modification.

CVSS severity5.9
Medium
EPSS probability0.76%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Race condition in the syslog engine of Cisco Identity Services Engine allows remote attackers to crash the Application Server process. Concurrent handling of high-rate syslog messages can trigger improper synchronization in the processing engine and terminate the Application Server. The interface must accept attacker-supplied syslog traffic at high volume; a successful attack interrupts ISE service without reported data disclosure or modification.

The record

CVE
CVE-2020-3353
Published
Jun 3, 2020
Updated
Nov 15, 2024
Vendor
ClamAV
Product
Cisco Identity Services Engine
Classifications
CWE-362, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 3, 2020CVE publishedPublication date reported by the CVE source.
  2. Nov 15, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco Identity Services Engineversion=n/a

Published CVSS scores

5.9Cisco Systems, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H/E:X/RL:X/RC:X
4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:N/A:P

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.

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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-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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