CVE-2021-29999Network attack vector

Unauthenticated memory corruption via DHCP stack overflow

Published Apr 13, 2021 · Updated Aug 3, 2024

Stack-based buffer overflow in Wind River VxWorks 6.8 and earlier allows remote attackers to corrupt memory via DHCP traffic. The public record identifies the DHCP server as the affected locus but does not disclose the parsing path, input field, or missing bounds operation. No authentication or user interaction is required over the network; published impact metrics cover data access, modification, and service interruption, but the exact outcome is undisclosed.

CVSS severity9.8
Critical
EPSS probability1.79%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack-based buffer overflow in Wind River VxWorks 6.8 and earlier allows remote attackers to corrupt memory via DHCP traffic. The public record identifies the DHCP server as the affected locus but does not disclose the parsing path, input field, or missing bounds operation. No authentication or user interaction is required over the network; published impact metrics cover data access, modification, and service interruption, but the exact outcome is undisclosed.

The record

CVE
CVE-2021-29999
Published
Apr 13, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 13, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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?

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

7.5NISTAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8NISTCVSS: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 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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