CVE-2026-6103EPSS p5.4%

CVE-2026-6103CVE-2026-6103

Description

phar_tar_number() parses the octal size field of a TAR header into a uint32_t with no overflow check. The field is 11 octal digits wide and holds values up to 0x1FFFFFFFF, so a size above 0xFFFFFFFF silently wraps. The parser then skips the wrong number of data blocks and interprets attacker-controlled file content as the next TAR header, which lets a crafted archive inject entries that PharData reports and extracts as if they were genuine.

Scoring

CVSS 4.3 ()
VectorCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
EPSS0.17% probability of exploitation · percentile 5.4% · 2026-10-05T12:00:23Z
Last modified2026-09-29
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.