{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","feed_url":"https://feed.craftedsignal.io/tags/cve-2026-8856/feed.json","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cpes":[],"_cs_cves":[{"cvss":7.7,"id":"CVE-2026-8856"}],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["HTTP Server 8.5","HTTP Server 9.0"],"_cs_severities":["medium"],"_cs_tags":["cve-2026-8856","dos","ibm"],"_cs_type":"threat","_cs_vendors":["IBM"],"content_html":"\u003cp\u003eIBM HTTP Server versions 8.5 and 9.0 are susceptible to a denial-of-service vulnerability, identified as CVE-2026-8856. This vulnerability arises in environments where an attacker has the ability to modify parts of the server\u0026rsquo;s configuration files. Exploitation could lead to uncontrolled resource consumption, causing the server to become unresponsive. This vulnerability was reported by IBM Corporation and impacts deployments where configuration file permissions are improperly managed, allowing unauthorized modifications.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAttacker gains write access to the IBM HTTP Server configuration files, potentially through compromised credentials or misconfigured permissions.\u003c/li\u003e\n\u003cli\u003eAttacker modifies the server configuration to introduce resource-intensive directives or modules.\u003c/li\u003e\n\u003cli\u003eThe server restarts or reloads the modified configuration.\u003c/li\u003e\n\u003cli\u003eThe server begins to execute the malicious configuration, consuming excessive resources like CPU, memory, or disk I/O.\u003c/li\u003e\n\u003cli\u003eLegitimate user requests are delayed or dropped due to resource exhaustion.\u003c/li\u003e\n\u003cli\u003eThe IBM HTTP Server becomes unresponsive, resulting in a denial-of-service condition.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of CVE-2026-8856 leads to a denial of service, rendering the IBM HTTP Server unavailable. The impact includes disruption of web services, loss of productivity, and potential damage to an organization\u0026rsquo;s reputation. The severity is amplified in environments where the affected server hosts critical applications or services.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eRestrict write access to IBM HTTP Server configuration files to authorized personnel only.\u003c/li\u003e\n\u003cli\u003eRegularly audit and review file permissions to prevent unauthorized modifications.\u003c/li\u003e\n\u003cli\u003eImplement file integrity monitoring on the server configuration directory to detect unexpected changes.\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rules provided in this brief to your SIEM to detect suspicious configuration changes or resource consumption patterns related to CVE-2026-8856.\u003c/li\u003e\n\u003cli\u003eMonitor system resource usage (CPU, memory, disk I/O) for anomalies that may indicate a denial-of-service attack related to this vulnerability.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-05-26T18:20:50Z","date_published":"2026-05-26T18:20:50Z","id":"https://feed.craftedsignal.io/briefs/2026-05-cve-2026-8856-ibm-http-dos/","summary":"IBM HTTP Server 8.5 and 9.0 is vulnerable to a denial of service (DoS) in configurations where an attacker possesses write access to server configuration files, as tracked by CVE-2026-8856.","title":"CVE-2026-8856 - IBM HTTP Server Denial of Service Vulnerability","url":"https://feed.craftedsignal.io/briefs/2026-05-cve-2026-8856-ibm-http-dos/"}],"language":"en","title":"CraftedSignal Threat Feed — Cve-2026-8856","version":"https://jsonfeed.org/version/1.1"}