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TI-2026-34294 Aliases CVE-2026-46643GHSA-vpr4-p6fq-85jc

Snappy: Binary path is never shell-escaped due to an inverted is_executable check

Priority HIGH 68CWE-78Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-78.

Summary

Snappy is a PHP library allowing thumbnail, snapshot or PDF generation from a url or a html page. Prior to version 1.7.1, on POSIX, escapeshellarg(‘/usr/bin/wkhtmltopdf’) returns the literal string ‘/usr/bin/wkhtmltopdf’ with the single-quote characters included. is_executable() then looks for a file whose actual name contains those quote characters, which essentially never exists. The safe branch is dead code and $command always falls through to the raw, unescaped value. The rest of the arguments (options, input, output) are escaped correctly, so injection has to land in the binary string itself. That happens whenever the binary path is sourced from configuration that is user-influenced, derived from environment variables that ultimately come from request data, or concatenated with any user-controlled fragment. This issue has been patched in version 1.7.1.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.002 9th percentileScored 2026-11-07
Fix Fixed snappy (KnpLabs): 1.7.1KnpLabs/knp-snappy (Packagist): 1.7.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
KnpLabssnappybefore 1.7.11.7.1Patch availableCNA
—KnpLabs/knp-snappy (Packagist)before 1.7.11.7.1Patch availableGHSA-vpr4-p6fq-85jc
  • snappy VendorKnpLabs Affected before 1.7.1 Fixed in 1.7.1 Patch available CNA
  • KnpLabs/knp-snappy (Packagist) Vendor— Affected before 1.7.1 Fixed in 1.7.1 Patch available GHSA-vpr4-p6fq-85jc

Remediation

  • Fix · CNA snappy (KnpLabs) Fixed in 1.7.1
  • Fix · GHSA-vpr4-p6fq-85jc KnpLabs/knp-snappy (Packagist) Fixed in 1.7.1 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-46643
  2. 2026-10-03 Alias added: GHSA-vpr4-p6fq-85jc

References

Advisory 1

Other 3

  • TI-2023-21930 Unsafe deserialization in knplabs/knp-snappy CVSS 3.1CRITICAL 9.8
  • TI-2023-12694 Snappy vulnerable to PHAR deserialization, allowing remote code execution CVSS 3.1CRITICAL 9.8
  • TI-2026-34314 Snappy: SSRF and local file read via the xsl-style-sheet option CVSS 4.0MEDIUM 6.9

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences