CVE-2026-84308: phpseclib — non-constant-time X25519 scalar multiplication permits full private-key recovery

medium Affects phpseclib/phpseclib. Feed 2026.10.29.1, updated 2026-10-28; published 2026-09-08; advisory modified 2026-09-29.

phpseclib — non-constant-time X25519 scalar multiplication permits full private-key recovery

Package: phpseclib/phpseclib Composer
Affected versions: <3.0.57 or >=4.0.0 and <4.0.1
Fixed in: 3.0.57, 4.0.1
Severity: medium CVSS 6.3
Exploitation: not on CISA KEV · EPSS 0% (25.7th percentile)
Published: 2026-09-08
Source: osv.dev

References

CWE-208 CWE-385

NVD record phpseclib/phpseclib advisories

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