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.
Affected products
php: php
References2
- github.com/php/php-src/security/advisories/GHSA-j3wh-g957-2m85 Vendor AdvisoryExploit
- github.com/php/php-src/security/advisories/GHSA-j3wh-g957-2m85 Vendor AdvisoryExploit
Metrics
- CVSS 3.1
-
3.3
LOW
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 5 · as of 9 November 2026
- CWE
- CWE-190
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