p PatchFirst

CVE-2026-55599

CVE-2026-55599 · phpseclib: X.509 certificate validation sends attacker-controlled outbound requests (server-side request forgery) via Authority Information Access

This page contains facts from public vulnerability sources. Check the original advisory before updating.

phpseclib is a PHP secure communications library. From 0.1.1 until 1.0.30, 2.0.55, and 3.0.54, when an application validates an untrusted X.509 certificate with phpseclib, X509::validateSignature() reads a URL out of that certificate's Authority Information Access (AIA) extension and connects to it. Attacker who supplies certificate fully controls host, port, and path of that connection. URL fetching is enabled by default, and no destination is blocked. An unauthenticated attacker can therefore make a validating server open connections to internal hosts and ports it should never reach, for example loopback 127.0.0.1, cloud metadata address 169.254.169.254, and internal-only services. This is a server-side request forgery (SSRF) caused by an insecure default. This vulnerability is fixed in 1.0.30, 2.0.55, and 3.0.54.

CVSS 5.8 · Medium · EPSS 0.2% · Fix available

Published
Updated

Stack: system · php

Affected products and versions

  • phpseclib

    Versions
    • >= 0.1.1, < 1.0.30: Affected
    • >= 2.0.0, < 2.0.55: Affected
    • >= 3.0.0, < 3.0.54: Affected

    No fix published

  • php-phpseclib Debian:12

    Versions
    • 2.0.42-1
    • 2.0.42-1+deb12u1
    • 2.0.42-1+deb12u2
    • 2.0.42-1+deb12u3
    • 2.0.42-1+deb12u5
    • 2.0.44-1
    • 2.0.45-1
    • 2.0.46-1
    • 2.0.47-1
    • 2.0.47-2
    • 2.0.47-3
    • 2.0.48-1
    • 2.0.48-2
    • 2.0.48-3
    • 2.0.49-1
    • 2.0.50-1
    • 2.0.51-1
    • 2.0.52-1
    • 2.0.53-1
    • 2.0.54-1
    • 2.0.55-1
    • 3.0.2-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • php-phpseclib Debian:13

    Versions
    • 2.0.48-3
    • 2.0.48-3+deb13u1
    • 2.0.48-3+deb13u3
    • 2.0.49-1
    • 2.0.50-1
    • 2.0.51-1
    • 2.0.52-1
    • 2.0.53-1
    • 2.0.54-1
    • 2.0.55-1
    • 3.0.2-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • php-phpseclib Debian:14

    Versions
    • 2.0.48-3
    • 2.0.49-1
    • 2.0.50-1
    • 2.0.51-1
    • 2.0.52-1
    • 2.0.53-1
    • 2.0.54-1
    Affected ranges
    • ECOSYSTEM: < 2.0.55-1

    Update to 2.0.55-1

  • php-phpseclib3 Debian:12

    Versions
    • 3.0.19-1
    • 3.0.19-1+deb12u1
    • 3.0.19-1+deb12u2
    • 3.0.19-1+deb12u3
    • 3.0.19-1+deb12u4
    • 3.0.19-1+deb12u6
    • 3.0.20-1
    • 3.0.21-1
    • 3.0.21-2
    • 3.0.22-1
    • 3.0.23-1
    • 3.0.33-1
    • 3.0.34-1
    • 3.0.35-1
    • 3.0.36-1
    • 3.0.37-1
    • 3.0.38-1
    • 3.0.39-1
    • 3.0.41-1
    • 3.0.42-1
    • 3.0.43-1
    • 3.0.43-2
    • 3.0.44-1
    • 3.0.44-2
    • 3.0.45-1
    • 3.0.46-1
    • 3.0.46-2
    • 3.0.47-1
    • 3.0.48-1
    • 3.0.49-1
    • 3.0.50-1
    • 3.0.51-1
    • 3.0.52-1
    • 3.0.52-2
    • 3.0.53-1
    • 3.0.55-1
    • 3.0.56-1
    • 3.0.57-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • php-phpseclib3 Debian:13

    Versions
    • 3.0.43-2
    • 3.0.43-2+deb13u1
    • 3.0.43-2+deb13u3
    • 3.0.44-1
    • 3.0.44-2
    • 3.0.45-1
    • 3.0.46-1
    • 3.0.46-2
    • 3.0.47-1
    • 3.0.48-1
    • 3.0.49-1
    • 3.0.50-1
    • 3.0.51-1
    • 3.0.52-1
    • 3.0.52-2
    • 3.0.53-1
    • 3.0.55-1
    • 3.0.56-1
    • 3.0.57-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • php-phpseclib3 Debian:14

    Versions
    • 3.0.43-2
    • 3.0.44-1
    • 3.0.44-2
    • 3.0.45-1
    • 3.0.46-1
    • 3.0.46-2
    • 3.0.47-1
    • 3.0.48-1
    • 3.0.49-1
    • 3.0.50-1
    • 3.0.51-1
    • 3.0.52-1
    • 3.0.52-2
    • 3.0.53-1
    Affected ranges
    • ECOSYSTEM: < 3.0.55-1

    Update to 3.0.55-1

  • phpseclib Debian:12

    Versions
    • 1.0.20-1
    • 1.0.20-1+deb12u1
    • 1.0.20-1+deb12u2
    • 1.0.20-1+deb12u3
    • 1.0.20-1+deb12u5
    • 1.0.21-1
    • 1.0.21-2
    • 1.0.22-1
    • 1.0.23-1
    • 1.0.23-2
    • 1.0.23-3
    • 1.0.23-4
    • 1.0.23-5
    • 1.0.23-6
    • 1.0.24-1
    • 1.0.27-1
    • 1.0.28-1
    • 1.0.29-1
    • 1.0.30-1
    • 2.0.0-1
    • 2.0.1-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • phpseclib Debian:13

    Versions
    • 1.0.23-6
    • 1.0.23-6+deb13u1
    • 1.0.23-6+deb13u3
    • 1.0.24-1
    • 1.0.27-1
    • 1.0.28-1
    • 1.0.29-1
    • 1.0.30-1
    • 2.0.0-1
    • 2.0.1-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • phpseclib/phpseclib Packagist

    Versions
    • 0.3.0
    • 0.3.1
    • 0.3.10
    • 0.3.5
    • 0.3.6
    • 0.3.7
    • 0.3.8
    • 0.3.9
    • 1.0.0
    • 1.0.1
    • 1.0.10
    • 1.0.11
    • 1.0.12
    • 1.0.13
    • 1.0.14
    • 1.0.15
    • 1.0.16
    • 1.0.17
    • 1.0.18
    • 1.0.19
    • 1.0.2
    • 1.0.20
    • 1.0.21
    • 1.0.22
    • 1.0.23
    • 1.0.24
    • 1.0.25
    • 1.0.26
    • 1.0.27
    • 1.0.28
    • 1.0.29
    • 1.0.3
    • 1.0.4
    • 1.0.5
    • 1.0.6
    • 1.0.7
    • 1.0.8
    • 1.0.9
    Affected ranges
    • ECOSYSTEM: ≥ 0.1.1, < 1.0.30

    Update to 1.0.30

  • phpseclib/phpseclib Packagist

    Versions
    • 2.0.0
    • 2.0.1
    • 2.0.10
    • 2.0.11
    • 2.0.12
    • 2.0.13
    • 2.0.14
    • 2.0.15
    • 2.0.16
    • 2.0.17
    • 2.0.18
    • 2.0.19
    • 2.0.2
    • 2.0.20
    • 2.0.21
    • 2.0.22
    • 2.0.23
    • 2.0.24
    • 2.0.25
    • 2.0.26
    • 2.0.27
    • 2.0.28
    • 2.0.29
    • 2.0.3
    • 2.0.30
    • 2.0.31
    • 2.0.32
    • 2.0.33
    • 2.0.34
    • 2.0.35
    • 2.0.36
    • 2.0.37
    • 2.0.38
    • 2.0.39
    • 2.0.4
    • 2.0.40
    • 2.0.41
    • 2.0.42
    • 2.0.43
    • 2.0.44
    • 2.0.45
    • 2.0.46
    • 2.0.47
    • 2.0.48
    • 2.0.49
    • 2.0.5
    • 2.0.50
    • 2.0.51
    • 2.0.52
    • 2.0.53
    • 2.0.54
    • 2.0.6
    • 2.0.7
    • 2.0.8
    • 2.0.9
    Affected ranges
    • ECOSYSTEM: ≥ 2.0.0, < 2.0.55

    Update to 2.0.55

  • phpseclib/phpseclib Packagist

    Versions
    • 3.0.0
    • 3.0.1
    • 3.0.10
    • 3.0.11
    • 3.0.12
    • 3.0.13
    • 3.0.14
    • 3.0.15
    • 3.0.16
    • 3.0.17
    • 3.0.18
    • 3.0.19
    • 3.0.2
    • 3.0.20
    • 3.0.21
    • 3.0.22
    • 3.0.23
    • 3.0.3
    • 3.0.33
    • 3.0.34
    • 3.0.35
    • 3.0.36
    • 3.0.37
    • 3.0.38
    • 3.0.39
    • 3.0.4
    • 3.0.40
    • 3.0.41
    • 3.0.42
    • 3.0.43
    • 3.0.44
    • 3.0.45
    • 3.0.46
    • 3.0.47
    • 3.0.48
    • 3.0.49
    • 3.0.5
    • 3.0.50
    • 3.0.51
    • 3.0.52
    • 3.0.53
    • 3.0.6
    • 3.0.7
    • 3.0.8
    • 3.0.9
    Affected ranges
    • ECOSYSTEM: ≥ 3.0.0, < 3.0.54

    Update to 3.0.54

  • phpseclib Ubuntu:Pro:16.04:LTS

    Versions
    • 0.3.10-3
    • 1.0.0-2
    • 1.0.0-3
    • 1.0.1-1
    • 1.0.1-3
    • 1.0.1-3ubuntu0.1
    • 1.0.1-3ubuntu0.1+esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • phpseclib Ubuntu:Pro:18.04:LTS

    Versions
    • 1.0.7-1
    • 1.0.8-1
    • 1.0.9-1
    • 1.0.9-1ubuntu0.1~esm1
    • 1.0.9-1ubuntu0.1~esm2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • phpseclib Ubuntu:Pro:20.04:LTS

    Versions
    • 1.0.16-2
    • 1.0.18-2
    • 1.0.18-2ubuntu0.1~esm1
    • 1.0.18-2ubuntu0.1~esm2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • phpseclib Ubuntu:22.04:LTS

    Versions
    • 1.0.19-3ubuntu2
    • 1.0.19-3ubuntu3
    • 1.0.20-1
    • 1.0.20-1ubuntu0.1~esm1
    • 1.0.20-1+deb12u3build0.22.04.1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • phpseclib Ubuntu:Pro:24.04:LTS

    Versions
    • 1.0.21-2
    • 1.0.22-1
    • 1.0.23-1
    • 1.0.23-1ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • phpseclib Ubuntu:25.10

    Versions
    • 1.0.23-6
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • phpseclib Ubuntu:26.10

    Versions
    • 1.0.24-1
    • 1.0.29-1
    • 1.0.30-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • phpseclib Ubuntu:Pro:26.04:LTS

    Versions
    • 1.0.23-6
    • 1.0.24-1
    • 1.0.24-1ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

Check your server →