CVE-2021-34734

Service interruption via LLDP double free

Published Aug 18, 2021 · Updated Nov 7, 2024

Double free in the LLDP implementation of Cisco Video Surveillance 7000 Series IP Cameras 2.12.4 allows remote attackers to force a reload. The LLDP implementation frees the same memory resource twice while processing a crafted LLDP packet, triggering the reload. The attacker must share the camera's Layer 2 broadcast domain, and successful exploitation interrupts service by rebooting the device.

CVSS severity6.5
Medium
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Double free in the LLDP implementation of Cisco Video Surveillance 7000 Series IP Cameras 2.12.4 allows remote attackers to force a reload. The LLDP implementation frees the same memory resource twice while processing a crafted LLDP packet, triggering the reload. The attacker must share the camera's Layer 2 broadcast domain, and successful exploitation interrupts service by rebooting the device.

The record

CVE
CVE-2021-34734
Published
Aug 18, 2021
Updated
Nov 7, 2024
Vendor
ClamAV
Product
Cisco Video Surveillance 7000 Series IP Cameras
Classifications
CWE-415, T1499
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 18, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 7, 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 vectoradjacent
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco Video Surveillance 7000 Series IP Camerasversion=n/a

Published CVSS scores

6.5Cisco Systems, Inc.CVSS:3.1/AV:A/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.

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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)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-415Double Free
T1499Endpoint Denial of Service

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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