unarr through 1.1.1 contains an off-by-one heap-based buffer overflow in tar_get_name() in tar/parse-tar.c, reachable through the ar_entry_get_name() API. Attackers can supply a crafted TAR archive with a full ustar prefix and name to write a NUL byte past the allocation, corrupting heap memory and crashing the process.
https://hackmd.io/@haind-pwn/unarr-tar-zip-oob
https://hackmd.io/@haind-pwn/cve-2026-111273-111274-unarr-tar-zip-oob
Published: 2026-10-15
Updated: 2026-10-16
Base Score: 5.6
Vector: CVSS2#AV:L/AC:L/Au:N/C:N/I:P/A:C
Severity: Medium
Base Score: 6.1
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
Severity: Medium
Base Score: 6.9
Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00143