CVE-2026-89653

Summary

In the Linux kernel, the following vulnerability has been resolved:

ceph: reject export_targets ranks >= CEPH_MAX_MDS in mdsmap decode

MDSMap export_targets entries are monitor controlled. check_new_map() uses each entry as a bit number in a fixed stack bitmap, so a rank outside the protocol namespace can make set_bit() write past the end of the array.

Reject ranks outside CEPH_MAX_MDS while decoding the map. Do not validate against possible_max_rank here because maps may legitimately reference ranks beyond a temporarily reduced max_mds.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxd517b3983dd3106ca92d6c5d0d09415a4a09481c < 736adee11af36e407ed902264f8b2fb5cf94b62faffected
LinuxLinuxd517b3983dd3106ca92d6c5d0d09415a4a09481c < 4d298880f82c42383b36946bafde7ccf4d804c9baffected
LinuxLinuxd517b3983dd3106ca92d6c5d0d09415a4a09481c < 96c3f5fbb0d5386e7111426f047f98cec4586674affected
LinuxLinuxd517b3983dd3106ca92d6c5d0d09415a4a09481c < aedc9053d909508a5f56c3f49f885fc030df4730affected
LinuxLinux5.15affected
LinuxLinux0 < 5.15unaffected
LinuxLinux6.12.109 <= 6.12.*unaffected
LinuxLinux6.18.50 <= 6.18.*unaffected
LinuxLinux7.2.4 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References