CVE-2026-40194 (GCVE-0-2026-40194)
Vulnerability from cvelistv5
Published
2026-04-10 20:24
Modified
2026-04-13 15:35
Severity ?
3.7 (Low) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
CWE
  • CWE-208 - Observable Timing Discrepancy
Summary
phpseclib is a PHP secure communications library. Prior to 3.0.51, 2.0.53, and 1.0.28, phpseclib\Net\SSH2::get_binary_packet() uses PHP's != operator to compare a received SSH packet HMAC against the locally computed HMAC. != on equal-length binary strings in PHP uses memcmp(), which short-circuits on the first differing byte. This is a real variable-time comparison (CWE-208), proven by scaling benchmarks. This vulnerability is fixed in 3.0.51, 2.0.53, and 1.0.28.
References
Impacted products
Vendor Product Version
phpseclib phpseclib Version: < 1.0.28
Version: >= 2.0.0, < 2.0.53
Version: >= 3.0.0, < 3.0.51
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