CVE-2026-22263 is a vulnerability identified in the Open Information Security Foundation's (OISF) Suricata network IDS/IPS/NSM engine, specifically affecting versions from 8.0.0 up to but not including 8.0.3. The root cause is an inefficiency in the parsing of HTTP/1 headers, which leads to excessive platform resource consumption within a processing loop. When Suricata processes multiple packets containing HTTP/1 headers, the inefficient parsing logic causes the system to slow down significantly, potentially degrading the performance of the IDS/IPS engine. This slowdown can affect the availability of Suricata’s monitoring and protective functions, potentially leading to delayed or missed detection of network threats. The vulnerability is categorized under CWE-1050, which relates to excessive resource consumption within loops. The CVSS v3.1 base score is 5.3 (medium severity), reflecting that the vulnerability can be exploited remotely without authentication or user interaction, but it only impacts availability without compromising confidentiality or integrity. The issue was patched in Suricata version 8.0.3, and no workarounds are currently known. There are no reports of active exploitation in the wild at this time.

For European organizations, the primary impact of CVE-2026-22263 is the potential degradation of network security monitoring and intrusion prevention capabilities due to Suricata’s slowed processing. This can lead to delayed detection of malicious activity or network anomalies, increasing the risk of successful cyberattacks. Organizations with high network traffic volumes or those relying heavily on Suricata for real-time threat detection may experience significant performance bottlenecks, potentially causing partial denial of service of their security infrastructure. Critical sectors such as finance, telecommunications, energy, and government agencies in Europe, which often deploy Suricata for network defense, could see reduced situational awareness and slower incident response times. While the vulnerability does not directly expose sensitive data or allow unauthorized access, the availability impact can indirectly increase risk by impairing security operations.

European organizations should promptly upgrade Suricata installations to version 8.0.3 or later to remediate this vulnerability. Given the lack of known workarounds, patching is the primary mitigation strategy. Network administrators should audit their current Suricata versions and prioritize updates in environments with high HTTP/1 traffic volumes. Additionally, monitoring system resource usage and Suricata performance metrics can help detect potential exploitation attempts or resource exhaustion conditions. Implementing rate limiting or traffic shaping on HTTP/1 flows upstream may reduce the risk of triggering the vulnerability. Organizations should also ensure that their incident response teams are aware of this issue to quickly identify and respond to any abnormal Suricata behavior. Finally, maintaining robust network segmentation and layered security controls will help mitigate the impact if Suricata’s availability is compromised.