9.1

CVE-2026-8856: ibm http_server Uncontrolled Resource Consumption

CVSS: 9.1v3.1CriticalAnalyzed
Published 26-05-2026Last modified 27-05-2026
Open JSON

Vulnerability summary

CVE-2026-8856 is a critical (CVSS 9.1) Uncontrolled Resource Consumption vulnerability in ibm http_server. EPSS estimates a 0.34% chance of exploitation in the next 30 days, higher than 26.1% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.1/10
010
Critical · v3.1 (NVD)
EPSS score
0.34%
0%100%
Low · +0.14 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 26-05-2026
    PublishedVulnerability first disclosed.
  2. 27-05-2026
    Last modifiedVulnerability information updated.

Description

IBM HTTP Server 8.5, and 9.0 is vulnerable to denial of service in configurations where an attacker has write access to parts of the server configuration.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.34%

Chance of exploitation in the next 30 days

Percentile

26%

Versus all other CVEs

30-day change

+0.14 pp

From 0.20% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.34%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ibm1 product
  • http_server≥ 8.5.0, ≤ Interim Fix 002 | 9.0 | ≥ 8.5.0.0, < 8.5.5.30 | ≥ 9.0.0.0, < 9.0.5.29

1 vendor · 1 product

References

1 links