The cache manager in the client in OpenAFS 1.0 through 1.4.8 and 1.5.0 through 1.5.58, and IBM AFS 3.6 before Patch 19, on Linux allows remote attackers to cause a denial of service (system crash) via an RX response with a large error-code value that is interpreted as a pointer and dereferenced, related to use of the ERR_PTR macro.