CVE-2026-6103

Summary

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.

Affected Software

VendorProductVersion RangeStatus
PHP GroupPHP8.2.* < 8.2.34affected
PHP GroupPHP8.3.* < 8.3.35affected
PHP GroupPHP8.4.* < 8.4.26affected
PHP GroupPHP8.5.* < 8.5.11affected

Weaknesses

  • CWE-190: CWE-190 Integer overflow or wraparound

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: poc
    • Automatable: no
    • Technical Impact: partial

Additional References

References