CVE-2023-41101Public exploitNetwork attack vector

Code execution via oversized pre-authentication query

Published Nov 17, 2023 · Updated Sep 4, 2024

Out-of-bounds write in OpenNDS before 10.1.3 allows remote attackers to execute arbitrary code or crash the captive portal via crafted GET requests. The get_query function in http_microhttpd.c copies cumulative pre-authentication query elements before verifying that their length fits QUERYMAXLEN, overflowing stack buffers in 9.x and earlier and heap buffers in 10.x. No authentication or user interaction is required; exploitation can interrupt Internet access through the portal or run code in the daemon context.

CVSS severity9.8
Critical
EPSS probability1.89%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds write in OpenNDS before 10.1.3 allows remote attackers to execute arbitrary code or crash the captive portal via crafted GET requests. The get_query function in http_microhttpd.c copies cumulative pre-authentication query elements before verifying that their length fits QUERYMAXLEN, overflowing stack buffers in 9.x and earlier and heap buffers in 10.x. No authentication or user interaction is required; exploitation can interrupt Internet access through the portal or run code in the daemon context.

The record

CVE
CVE-2023-41101
Published
Nov 17, 2023
Updated
Sep 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 17, 2023CVE publishedPublication date reported by the CVE source.
  2. Sep 4, 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

9.8UbuntuCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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 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-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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