Heap-based buffer overflow in the SOHM list-index deserialization code in HDF5 through 2.1.1 on all platforms allows attackers to cause a denial of service (crash) via a crafted HDF5 file whose shared-message list index declares a num_messages count exceeding list_max, triggering out-of-bounds heap reads and writes in H5SM__cache_list_deserialize and H5SM__cache_list_verify_chksum.
Published: 2026-07-27
Updated: 2026-08-18
Base Score: 4.9
Vector: CVSS2#AV:L/AC:L/Au:N/C:N/I:N/A:C
Severity: Medium
Base Score: 5.5
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Severity: Medium
Base Score: 8.2
Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:H/SC:N/SI:L/SA:H
Severity: High
EPSS: 0.00119