CVE-2026-6103 (GCVE-0-2026-6103)

Vulnerability from cvelistv5 – Published: 2026-09-25 20:08 – Updated: 2026-09-25 20:41
VLAI
Title
Phar TAR phar_tar_number() Integer Overflow - Archive Entry Injection
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.
Severity
4.3 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-25 20:41 UTC
CWE
  • CWE-190 - Integer overflow or wraparound
Assigner
php CNA under the mitre root
CNA scorecard B 80/100 over 25 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
PHP Group PHP Affected: 8.2.* , < 8.2.34 (semver)
Affected: 8.3.* , < 8.3.35 (semver)
Affected: 8.4.* , < 8.4.26 (semver)
Affected: 8.5.* , < 8.5.11 (semver)
guessed Create a notification for this product.
Credits
@arnoldasr (GitHub) @Oblivionsage (GitHub) @OSTIF-Derek (GitHub) Jakub Zelenka Weilin Du
Show details on NVD website
To clipboard 

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