Vulnerability-Lookup

CVE-2026-4177 (GCVE-0-2026-4177)

Vulnerability from cvelistv5 – Published: 2026-03-16 22:30 – Updated: 2026-07-15 00:58

Title

YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter

Summary

YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter. The heap overflow occurs when class names exceed the initial 512-byte allocation. The base64 decoder could read past the buffer end on trailing newlines. strtok mutated n->type_id in place, corrupting shared node data. A memory leak occurred in syck_hdlr_add_anchor when a node already had an anchor. The incoming anchor string 'a' was leaked on early return.

Severity

9.1 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

7.3 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-03-17 14:04 UTC

CWE

CWE-122 - Heap-based Buffer Overflow
CWE-120 - Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

Assigner

CPANSec CNA under the redhat root

CNA scorecard C 61/100 over 360 records in the last 180 days details

References

8 references

URL	Tags
https://github.com/cpan-authors/YAML-Syck/commit/…	patch
https://metacpan.org/release/TODDR/YAML-Syck-1.37…	release-notes
http://www.openwall.com/lists/oss-security/2026/03/16/6
https://access.redhat.com/security/cve/CVE-2026-4177	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2448277	issue-trackingx_refsource_REDHAT
https://security.access.redhat.com/data/csaf/v2/v…	x_sadp-csaf-vex
https://access.redhat.com/errata/RHSA-2026:8311	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:6470	vendor-advisoryx_refsource_REDHAT

Impacted products

4 products

Vendor	Product	Version	CPE status
TODDR	YAML::Syck	Affected: 0 , ≤ 1.36 (custom)	guessed
Red Hat	Red Hat Enterprise Linux 7 Extended Lifecycle Support	Unaffected: 0:1.27-3.el7_9.1 , < * (rpm) cpe:/o:redhat:rhel_els:7
Red Hat	Red Hat Enterprise Linux 8	Unaffected: 0:1.30-6.el8_10 , < * (rpm) cpe:/a:redhat:enterprise_linux:8::crb
Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:enterprise_linux:6

Credits

Todd Rinaldo

Show details on NVD website

JSON

To clipboard

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ALSA-2026:6470 (CVE-2026-4177)

Vulnerability from osv_almalinux – Published: 2026-04-02 00:00 – Updated: 2026-04-03 12:07 – Source website

Summary

Important: perl-YAML-Syck security update

Details

This module provides a Perl interface to the libsyck data serialization library. It exports the Dump and Load functions for converting Perl data structures to YAML strings, and the other way around.

Security Fix(es):

perl-YAML-Syck: YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter (CVE-2026-4177)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

References

URL

Type

	https://access.redhat.com/errata/RHSA-2026:6470	ADVISORY
	https://access.redhat.com/security/cve/CVE-2026-4177	REPORT
	https://bugzilla.redhat.com/2448277	REPORT
	https://errata.almalinux.org/8/ALSA-2026-6470.html	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "AlmaLinux:8",
        "name": "perl-YAML-Syck"
      },
      "ranges": [
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          "events": [
            {
              "introduced": "0"
            },
            {
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            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "This module provides a Perl interface to the libsyck data serialization library. It exports the Dump and Load functions for converting Perl data structures to YAML strings, and the other way around.  \n\nSecurity Fix(es):  \n\n  * perl-YAML-Syck: YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter (CVE-2026-4177)\n\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.\n",
  "id": "ALSA-2026:6470",
  "modified": "2026-04-03T12:07:59Z",
  "published": "2026-04-02T00:00:00Z",
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    },
    {
      "type": "ADVISORY",
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    }
  ],
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  "schema_version": "1.7.0",
  "summary": "Important: perl-YAML-Syck security update",
  "upstream": [
    "CVE-2026-4177"
  ]
}

FKIE_CVE-2026-4177

Vulnerability from fkie_nvd - Published: 2026-03-16 23:16 - Updated: 2026-07-15 02:22

Severity

9.1 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
7.3 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Summary

References

URL	Tags
9b29abf9-4ab0-4765-b253-1875cd9b441e	https://github.com/cpan-authors/YAML-Syck/commit/e8844a31c8cf0052914b198fc784ed4e6b8ae69e.patch	Patch
9b29abf9-4ab0-4765-b253-1875cd9b441e	https://metacpan.org/release/TODDR/YAML-Syck-1.37_01/changes#L21	Release Notes
af854a3a-2127-422b-91ae-364da2661108	http://www.openwall.com/lists/oss-security/2026/03/16/6	Mailing List, Third Party Advisory
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:6470
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:8311
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/security/cve/CVE-2026-4177
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://bugzilla.redhat.com/show_bug.cgi?id=2448277
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4177.json

Impacted products

	Vendor	Product	Version
	toddr	yaml\	\

JSON

To clipboard

{
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    }
  ],
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  "references": [
    {
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/cpan-authors/YAML-Syck/commit/e8844a31c8cf0052914b198fc784ed4e6b8ae69e.patch"
    },
    {
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
      "tags": [
        "Release Notes"
      ],
      "url": "https://metacpan.org/release/TODDR/YAML-Syck-1.37_01/changes#L21"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Mailing List",
        "Third Party Advisory"
      ],
      "url": "http://www.openwall.com/lists/oss-security/2026/03/16/6"
    },
    {
      "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
      "url": "https://access.redhat.com/errata/RHSA-2026:6470"
    },
    {
      "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
      "url": "https://access.redhat.com/errata/RHSA-2026:8311"
    },
    {
      "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
      "url": "https://access.redhat.com/security/cve/CVE-2026-4177"
    },
    {
      "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2448277"
    },
    {
      "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4177.json"
    }
  ],
  "sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-122"
        }
      ],
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-120"
        }
      ],
      "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
      "type": "Secondary"
    }
  ]
}

GHSA-72R6-P2X3-G9GJ

Vulnerability from github – Published: 2026-03-17 00:31 – Updated: 2026-06-30 03:35

Details

YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter.

The heap overflow occurs when class names exceed the initial 512-byte allocation.

The base64 decoder could read past the buffer end on trailing newlines.

strtok mutated n->type_id in place, corrupting shared node data.

A memory leak occurred in syck_hdlr_add_anchor when a node already had an anchor. The incoming anchor string 'a' was leaked on early return.

Severity

9.1 (Critical)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-4177"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-120",
      "CWE-122"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-03-16T23:16:21Z",
    "severity": "CRITICAL"
  },
  "details": "YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter.\n\nThe heap overflow occurs when class names exceed the initial 512-byte allocation.\n\nThe base64 decoder could read past the buffer end on trailing newlines.\n\nstrtok mutated n-\u003etype_id in place, corrupting shared node data.\n\nA memory leak occurred in syck_hdlr_add_anchor when a node already had an anchor. The incoming anchor string \u0027a\u0027 was leaked on early return.",
  "id": "GHSA-72r6-p2x3-g9gj",
  "modified": "2026-06-30T03:35:55Z",
  "published": "2026-03-17T00:31:34Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-4177"
    },
    {
      "type": "WEB",
      "url": "https://github.com/cpan-authors/YAML-Syck/commit/e8844a31c8cf0052914b198fc784ed4e6b8ae69e.patch"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:6470"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:8311"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-4177"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2448277"
    },
    {
      "type": "WEB",
      "url": "https://metacpan.org/release/TODDR/YAML-Syck-1.37_01/changes#L21"
    },
    {
      "type": "WEB",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4177.json"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2026/03/16/6"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

MSRC_CVE-2026-4177

Vulnerability from csaf_microsoft - Published: 2026-10-21 01:01 - Updated: 2026-10-28 01:45

Summary

YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter

Scope

1 vulnerability in this advisory, including CVE-2026-4177.

CVE-2026-4177

Known not affected: 1 product

Open the full advisory

OPENSUSE-SU-2026:10551-1

Vulnerability from csaf_opensuse - Published: 2026-04-15 00:00 - Updated: 2026-09-17 17:01

Summary

perl-YAML-Syck-1.440.0-1.1 on GA media

Severity

Moderate

Scope

1 vulnerability in this advisory, including CVE-2026-4177.

CVE-2026-4177

Recommended: 4 products

Open the full advisory

OPENSUSE-SU-2026:20771-1

Vulnerability from csaf_opensuse - Published: 2026-05-19 14:01 - Updated: 2026-09-17 17:32

Summary

Security update for perl-YAML-Syck

Severity

Critical

Scope

2 vulnerabilities in this advisory, including CVE-2026-4177.

CVE-2026-4177

Recommended: 4 products

Open the full advisory

RHSA-2026:6470

Vulnerability from csaf_redhat - Published: 2026-04-02 12:23 - Updated: 2026-11-05 21:27

Summary

Red Hat Security Advisory: perl-YAML-Syck security update

Severity

Important

Scope

1 vulnerability in this advisory, including CVE-2026-4177.

CVE-2026-4177

Multiple security issues have been discovered in the perl YAML::Syck module. A heap overflow occurs when class names exceed the initial 512-byte allocation, a base64 decoder could read past the buffer end on trailing newlines. strtok mutated n->type_id in place, corrupting shared node data, and a memory leak occurred in syck_hdlr_add_anchor when a node already had an anchor. The incoming anchor string 'a' was leaked on early return.

7.3 (High)


                
                  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Fixed: 13 products

https://access.redhat.com/errata/RHSA-2026:6470

Open the full advisory

RHSA-2026:8311

Vulnerability from csaf_redhat - Published: 2026-04-15 13:54 - Updated: 2026-11-05 21:27

Summary

Red Hat Security Advisory: perl-YAML-Syck security update

Severity

Important

Scope

1 vulnerability in this advisory, including CVE-2026-4177.

CVE-2026-4177

7.3 (High)


                
                  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Fixed: 9 products

https://access.redhat.com/errata/RHSA-2026:8311

Open the full advisory

UBUNTU-CVE-2026-4177 (CVE-2026-4177)

Vulnerability from osv_ubuntu – Published: 2026-03-16 23:16 – Updated: 2026-10-17 09:37 – Source website

Details

Severity

9.1 (Critical)


                    
                      CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

7.3 (High)


                    
                      CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-4177	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-4177	REPORT
	https://lists.security.metacpan.org/cve-announce/…	REPORT
	https://github.com/cpan-authors/YAML-Syck/commit/…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libyaml-syck-perl",
            "binary_version": "1.29-1ubuntu0.16.04.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "libyaml-syck-perl",
        "purl": "pkg:deb/ubuntu/libyaml-syck-perl@1.29-1ubuntu0.16.04.1~esm1?arch=source\u0026distro=esm-apps/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.27-2build2",
        "1.29-1",
        "1.29-1build1",
        "1.29-1ubuntu0.16.04.1~esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libyaml-syck-perl",
            "binary_version": "1.29-1ubuntu0.18.04.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "libyaml-syck-perl",
        "purl": "pkg:deb/ubuntu/libyaml-syck-perl@1.29-1ubuntu0.18.04.1~esm1?arch=source\u0026distro=esm-apps/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.29-1build3",
        "1.29-1ubuntu0.18.04.1~esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libyaml-syck-perl",
            "binary_version": "1.31-1ubuntu0.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "libyaml-syck-perl",
        "purl": "pkg:deb/ubuntu/libyaml-syck-perl@1.31-1ubuntu0.1~esm1?arch=source\u0026distro=esm-apps/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.31-1",
        "1.31-1build1",
        "1.31-1ubuntu0.1~esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libyaml-syck-perl",
            "binary_version": "1.34-1ubuntu0.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:22.04:LTS",
        "name": "libyaml-syck-perl",
        "purl": "pkg:deb/ubuntu/libyaml-syck-perl@1.34-1ubuntu0.1~esm1?arch=source\u0026distro=esm-apps/jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.34-1build1",
        "1.34-1build2",
        "1.34-1ubuntu0.1~esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libyaml-syck-perl",
            "binary_version": "1.34-2ubuntu0.24.04.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:24.04:LTS",
        "name": "libyaml-syck-perl",
        "purl": "pkg:deb/ubuntu/libyaml-syck-perl@1.34-2ubuntu0.24.04.1~esm1?arch=source\u0026distro=esm-apps/noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.34-2",
        "1.34-2build1",
        "1.34-2build2",
        "1.34-2build3",
        "1.34-2ubuntu0.24.04.1~esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libyaml-syck-perl",
            "binary_version": "1.34-3ubuntu0.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "libyaml-syck-perl",
        "purl": "pkg:deb/ubuntu/libyaml-syck-perl@1.34-3ubuntu0.1?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.34-2build4",
        "1.34-3",
        "1.34-3ubuntu0.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libyaml-syck-perl",
            "binary_version": "1.47-1build1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.10",
        "name": "libyaml-syck-perl",
        "purl": "pkg:deb/ubuntu/libyaml-syck-perl@1.47-1build1?arch=source\u0026distro=stonking"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.36-1",
        "1.36-3",
        "1.47-1",
        "1.47-1build1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libyaml-syck-perl",
            "binary_version": "1.36-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "libyaml-syck-perl",
        "purl": "pkg:deb/ubuntu/libyaml-syck-perl@1.36-1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.34-3",
        "1.34-4",
        "1.36-1"
      ]
    }
  ],
  "aliases": [],
  "details": "YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter. The heap overflow occurs when class names exceed the initial 512-byte allocation. The base64 decoder could read past the buffer end on trailing newlines. strtok mutated n-\u003etype_id in place, corrupting shared node data. A memory leak occurred in syck_hdlr_add_anchor when a node already had an anchor. The incoming anchor string \u0027a\u0027 was leaked on early return.",
  "id": "UBUNTU-CVE-2026-4177",
  "modified": "2026-10-17T09:37:50Z",
  "published": "2026-03-16T23:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-4177"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-4177"
    },
    {
      "type": "REPORT",
      "url": "https://lists.security.metacpan.org/cve-announce/msg/38035745/"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/cpan-authors/YAML-Syck/commit/e8844a31c8cf0052914b198fc784ed4e6b8ae69e"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-4177"
  ]
}

WID-SEC-W-2026-0939

Vulnerability from csaf_certbund - Published: 2026-03-31 22:00 - Updated: 2026-05-31 22:00

Summary

cPanel cPanel/WHM (perl-YAML-Syck): Schwachstelle ermöglicht Codeausführung und DoS

Severity

Hoch

Scope

1 vulnerability in this advisory, including CVE-2026-4177.

CVE-2026-4177

Known affected: 11 products

Open the full advisory

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

Order JSON

How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Publication & reservation Sightings KEV catalogs Other timestamps

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

CVE-2026-4177 (GCVE-0-2026-4177)

ALSA-2026:6470 (CVE-2026-4177)

UBUNTU-CVE-2026-4177 (CVE-2026-4177)

Tags

Sightings

Nomenclature

Vulnerability timeline

Related by attack behaviour