CVE-2021-45039Public exploitNetwork attack vector

Pre-authentication code execution via UDP buffer overflow

Published May 31, 2023 · Updated Jan 10, 2025

Buffer overflow in Uniview IP camera firmware allows remote attackers to execute code through a crafted message sent to UDP port 7788. The maintain daemon's TLV case 10 passes attacker-controlled text to an unbounded %[^:] sscanf conversion targeting a fixed stack buffer. Reachability requires network access to UDP 7788; successful exploitation starts telnetd and grants root access through unchanged hardcoded credentials.

CVSS severity9.8
Critical
EPSS probability4.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in Uniview IP camera firmware allows remote attackers to execute code through a crafted message sent to UDP port 7788. The maintain daemon's TLV case 10 passes attacker-controlled text to an unbounded %[^:] sscanf conversion targeting a fixed stack buffer. Reachability requires network access to UDP 7788; successful exploitation starts telnetd and grants root access through unchanged hardcoded credentials.

The record

CVE
CVE-2021-45039
Published
May 31, 2023
Updated
Jan 10, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-120, CAPEC-100, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 31, 2023CVE publishedPublication date reported by the CVE source.
  2. Jan 10, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8CISA VulnrichmentCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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 exploitPublished

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
CAPEC-100Overflow Buffers
T1190Exploit Public-Facing Application

Public exploit references

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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