CVE-2026-6103 Affecting php84 package, versions <8.4.27-r0


Severity

Recommended
0.0
low
0
10

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Threat Intelligence

EPSS
0.16% (5th percentile)

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  • Snyk IDSNYK-ALPINE322-PHP84-21430988
  • published22 Oct 2026
  • disclosed25 Sept 2026

Introduced: 25 Sep 2026

NewCVE-2026-6103  (opens in a new tab)

How to fix?

Upgrade Alpine:3.22 php84 to version 8.4.27-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream php84 package and not the php84 package as distributed by Alpine. See How to fix? for Alpine:3.22 relevant fixed versions and status.

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 Base Scores

version 3.1