Published: August 5, 2026 | Last Modified: August 5, 2026
In OpenStack Swift through 2.38.0, the proxy server Accept header parser contains a regular expression vulnerable to catastrophic backtracking (ReDoS). The "qdtext" pattern (?:[^"]|\\.)* allows an unauthenticated remote attacker to send a crafted Accept header that causes exponential CPU consumption in the proxy worker. A payload of 32 backslash-character pairs exceeds 30 seconds of CPU time. No authentication is required. Repeated requests can exhaust all proxy worker threads, resulting in a complete denial of service.
This analysis is generated by Ghostwire from NVD, CISA KEV, EPSS, and open-source intelligence data. Verify findings through primary sources before acting.