CVE-2026-8850Network attack vector

Unauthenticated service interruption via mod_ibm_upload null dereference

Published May 26, 2026 · Updated May 26, 2026

Denial of service in IBM HTTP Server 8.5 and 9.0 allows remote attackers to interrupt service through optional mod_ibm_upload. The module dereferences a null pointer, but IBM has not disclosed the request field, code path, or invalid state that produces the null value. The server must load and configure the optional upload module; exploitation requires no authentication or user interaction and affects availability only.

CVSS severity7.5
High
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in IBM HTTP Server 8.5 and 9.0 allows remote attackers to interrupt service through optional mod_ibm_upload. The module dereferences a null pointer, but IBM has not disclosed the request field, code path, or invalid state that produces the null value. The server must load and configure the optional upload module; exploitation requires no authentication or user interaction and affects availability only.

The record

CVE
CVE-2026-8850
Published
May 26, 2026
Updated
May 26, 2026
Vendor
OpenBMC Project
Product
IBM HTTP Server
Classifications
CWE-476, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 26, 2026CVE publishedPublication date reported by the CVE source.
  2. May 26, 2026Record 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=8.5.0 <=Interim Fix 002
  2. Affected versionversion=9.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

OpenBMC Project · IBM HTTP Serverversion=8.5.0 <=Interim Fix 002; version=9.0

Published CVSS scores

7.5IBMCVSS:3.1/AV:N/AC:L/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.

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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 exploitUnconfirmed

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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