CVE-2026-54399
High
Description
Uncontrolled Resource Consumption vulnerability in the HTTP/1.1 message parser in Apache HttpComponents Core (5.4.2 and earlier, 5.5-beta1 and earlier) allows an remote attacker to cause a denial of service through memory exhaustion by sending messages with excessive number of headers / excessive header length
SeverityHigh
CVSS7.5
Exploit probability—
Product
Apache Httpcomponents Core
PublishedJul 1, 2026
First seenJul 1, 2026
Weakness typeCWE-400Uncontrolled resource consumption
How to fix
Update
- org.apache.httpcomponents.core5:httpcore55.4.3, 5.5-beta2 or later
Vendor advisories
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| apache httpcomponents_core | 5.0 ≤ v ≤ 5.4.2, 5.5 | — |
| org.apache.httpcomponents.core5:httpcore5Maven | v < 5.4.3, 5.5-alpha1 ≤ v < 5.5-beta2 | 5.4.3, 5.5-beta2 |
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