CVE-2023-33626Public exploitNetwork attack vector

Pre-auth code execution via unchecked header copy

Published Jun 12, 2023 · Updated Jan 3, 2025

Stack overflow in gena.cgi in D-Link DIR-600 B5 firmware 2.18 allows remote attackers to execute code via a crafted HTTP request header. The CGI parser copies the header's query field into a 512-byte stack buffer without validating the supplied length. The HTTP interface is reachable before authentication, and oversized input can corrupt the stack and yield arbitrary code execution on the router.

CVSS severity9.8
Critical
EPSS probability1.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack overflow in gena.cgi in D-Link DIR-600 B5 firmware 2.18 allows remote attackers to execute code via a crafted HTTP request header. The CGI parser copies the header's query field into a 512-byte stack buffer without validating the supplied length. The HTTP interface is reachable before authentication, and oversized input can corrupt the stack and yield arbitrary code execution on the router.

The record

CVE
CVE-2023-33626
Published
Jun 12, 2023
Updated
Jan 3, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 12, 2023CVE publishedPublication date reported by the CVE source.
  2. Jan 3, 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

9.8NIST NVDCVSS: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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-787Out-of-bounds Write
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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