CVE-2023-26281Network attack vector

Unauthenticated service interruption via crafted URL

Published Feb 28, 2023 · Updated Mar 6, 2025

Improper input validation in IBM HTTP Server 8.5 allows remote attackers to interrupt service with a specially crafted URL. IBM has not published the affected request-processing locus or the validation operation performed incorrectly on the URL. Exploitation requires no authentication or user interaction, but IBM rates attack complexity as high and reports availability impact only.

CVSS severity7.5
High
EPSS probability1.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in IBM HTTP Server 8.5 allows remote attackers to interrupt service with a specially crafted URL. IBM has not published the affected request-processing locus or the validation operation performed incorrectly on the URL. Exploitation requires no authentication or user interaction, but IBM rates attack complexity as high and reports availability impact only.

The record

CVE
CVE-2023-26281
Published
Feb 28, 2023
Updated
Mar 6, 2025
Vendor
OpenBMC Project
Product
IBM HTTP Server
Classifications
CWE-20, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 28, 2023CVE publishedPublication date reported by the CVE source.
  2. Mar 6, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=8.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

OpenBMC Project · IBM HTTP Serverversion=8.5

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5.9IBM CorporationCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/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 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 exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1499Endpoint Denial of Service

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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