Vulnerability-Lookup

GHSA-P57R-8PG4-2892

Vulnerability from github – Published: 2026-05-19 15:31 – Updated: 2026-05-19 15:31

Details

HestiaCP versions 1.9.0 through 1.9.4 contain a deserialization vulnerability in the web terminal component caused by a session format mismatch between PHP and Node.js that allows unauthenticated remote attackers to achieve root-level code execution. Attackers can inject crafted data into HTTP headers that are processed by the PHP session handler but incorrectly deserialized by the Node.js web terminal component as trusted session values, resulting in arbitrary command execution on systems with the web terminal feature enabled.

Severity

10.0 (Critical)


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

9.5 (Critical)


                  
                    CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-43633"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-502"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-19T14:16:43Z",
    "severity": "CRITICAL"
  },
  "details": "HestiaCP versions 1.9.0 through 1.9.4 contain a deserialization vulnerability in the web terminal component caused by a session format mismatch between PHP and Node.js that allows unauthenticated remote attackers to achieve root-level code execution. Attackers can inject crafted data into HTTP headers that are processed by the PHP session handler but incorrectly deserialized by the Node.js web terminal component as trusted session values, resulting in arbitrary command execution on systems with the web terminal feature enabled.",
  "id": "GHSA-p57r-8pg4-2892",
  "modified": "2026-05-19T15:31:31Z",
  "published": "2026-05-19T15:31:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43633"
    },
    {
      "type": "WEB",
      "url": "https://github.com/hestiacp/hestiacp/issues/5229"
    },
    {
      "type": "WEB",
      "url": "https://github.com/hestiacp/hestiacp/pull/5244"
    },
    {
      "type": "WEB",
      "url": "https://github.com/hestiacp/hestiacp/commit/854d71b3c1737b0a0d0cc55c926008ffe1f6719b"
    },
    {
      "type": "WEB",
      "url": "https://mercuryiss.com.au/hestiacp-unauthenticated-rce-ip-spoofing-cve-2026-43633-cve-2026-43634"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/hestiacp-deserialization-rce-via-web-terminal"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-43633 (GCVE-0-2026-43633)

Vulnerability from cvelistv5 – Published: 2026-05-19 13:29 – Updated: 2026-05-19 14:00 X_Open Source

Title

HestiaCP 1.9.0-1.9.4 Deserialization RCE via Web Terminal

Summary

Severity

9.5 (Critical)


                        
                          CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

10 (Critical)


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

CWE

CWE-502 - Deserialization of Untrusted Data

Assigner

VulnCheck

References

5 references

URL	Tags
https://mercuryiss.com.au/hestiacp-unauthenticate…	technical-descriptionexploit
https://github.com/hestiacp/hestiacp/issues/5229	issue-tracking
https://github.com/hestiacp/hestiacp/pull/5244	issue-tracking
https://github.com/hestiacp/hestiacp/commit/854d7…	patch
https://www.vulncheck.com/advisories/hestiacp-des…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
hestiacp	hestiacp	Affected: 1.9.0 , ≤ 1.9.4 (semver) Unaffected: 854d71b3c1737b0a0d0cc55c926008ffe1f6719b (git)

Date Public

2026-03-09 00:00

Credits

sutol divinity76

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-43633",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-19T13:59:09.185218Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-19T14:00:36.715Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "affected",
          "product": "hestiacp",
          "repo": "https://github.com/hestiacp/hestiacp",
          "vendor": "hestiacp",
          "versions": [
            {
              "lessThanOrEqual": "1.9.4",
              "status": "affected",
              "version": "1.9.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "854d71b3c1737b0a0d0cc55c926008ffe1f6719b",
              "versionType": "git"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "sutol"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "divinity76"
        }
      ],
      "datePublic": "2026-03-09T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
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            }
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      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 9.5,
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            "exploitMaturity": "NOT_DEFINED",
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            "providerUrgency": "NOT_DEFINED",
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            "subConfidentialityImpact": "HIGH",
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            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
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          "scenarios": [
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            "integrityImpact": "HIGH",
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            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
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          "scenarios": [
            {
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      "problemTypes": [
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      "providerMetadata": {
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        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
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      },
      "references": [
        {
          "tags": [
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            "exploit"
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          "url": "https://mercuryiss.com.au/hestiacp-unauthenticated-rce-ip-spoofing-cve-2026-43633-cve-2026-43634"
        },
        {
          "tags": [
            "issue-tracking"
          ],
          "url": "https://github.com/hestiacp/hestiacp/issues/5229"
        },
        {
          "tags": [
            "issue-tracking"
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          "url": "https://github.com/hestiacp/hestiacp/pull/5244"
        },
        {
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        },
        {
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          ],
          "url": "https://www.vulncheck.com/advisories/hestiacp-deserialization-rce-via-web-terminal"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "tags": [
        "x_open-source"
      ],
      "title": "HestiaCP 1.9.0-1.9.4 Deserialization RCE via Web Terminal",
      "x_generator": {
        "engine": "vulncheck"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-43633",
    "datePublished": "2026-05-19T13:29:55.780Z",
    "dateReserved": "2026-05-01T18:22:45.641Z",
    "dateUpdated": "2026-05-19T14:00:36.715Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-P57R-8PG4-2892

CVE-2026-43633 (GCVE-0-2026-43633)

Tags

Sightings

Nomenclature