CVE-2026-6103
lowpriority · track · 13EPSS 0.002 · 5 %ileDEUSEPSS · scored 2026-10-28
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.1–4.3
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (28)
Products and version ranges known to be affected.
advisories (4)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-3585PHP: Mehrere SchwachstellenDeutsch2026-09-24csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in PHP ausnutzen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen oder die Integrität zu verletzen.
- BIT-libphp-2026-6103Phar TAR phar_tar_number() Integer Overflow - Archive Entry Injection2026-10-01vendor · osvUS
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.
- BIT-php-2026-6103Phar TAR phar_tar_number() Integer Overflow - Archive Entry Injection2026-10-01vendor · osvUS
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.
- BIT-php-min-2026-6103Phar TAR phar_tar_number() Integer Overflow - Archive Entry Injection2026-10-01vendor · osvUS
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.
also known as (4)
Other names and identifiers for this entity.
- BIT-libphp-2026-6103osv
- BIT-php-2026-6103osv
- BIT-php-min-2026-6103osv
- GHSA-j3wh-g957-2m85osv
sources
Which sources assert this record, and when.
references (1) nvd
External citations — patches, advisories, analysis.
- https://github.com/php/php-src/security/advisories/GHSA-j3wh-g957-2m85Vendor AdvisoryExploit
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