Libyal libpff through 20260926 contains an integer underflow in libpff_record_entry_get_multi_value() that allows attackers to trigger heap out-of-bounds reads via non-monotonic multi-value offsets. Attackers can craft PST, OST or PAB files with decreasing PT_MV_STRING8, PT_MV_UNICODE or PT_MV_BINARY offsets to crash libpff, pypff or pffexport and expose adjacent heap memory.
https://hackmd.io/@haind-pwn/libpff-multivalue-offset-underflow-oob-read
Published: 2026-10-14
Updated: 2026-10-16
Base Score: 5.6
Vector: CVSS2#AV:L/AC:L/Au:N/C:P/I:N/A:C
Severity: Medium
Base Score: 6.1
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H
Severity: Medium
Base Score: 6.9
Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00171