Vulnerability-Lookup

GHSA-2VRR-CGR4-GFMM

Vulnerability from github – Published: 2026-09-17 18:31 – Updated: 2026-09-17 18:31

Details

b2evolution CMS versions 6.7.8 through 7.2.5 contain an incomplete fix for CVE-2016-8901 where the serialized-array object check in param_check_serialized_array() fails to reject payloads with negative integer array keys. Unauthenticated attackers can submit crafted serialized PHP objects via POST requests to htsrv/call_plugin.php that bypass validation and reach unserialize(), instantiating arbitrary PHP objects with attacker-chosen properties that may enable code execution if suitable POP gadget chains exist.

Severity

8.1 (High)


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

9.2 (Critical)


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

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-76834"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-502"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-17T16:17:42Z",
    "severity": "CRITICAL"
  },
  "details": "b2evolution CMS versions 6.7.8 through 7.2.5 contain an incomplete fix for CVE-2016-8901 where the serialized-array object check in param_check_serialized_array() fails to reject payloads with negative integer array keys. Unauthenticated attackers can submit crafted serialized PHP objects via POST requests to htsrv/call_plugin.php that bypass validation and reach unserialize(), instantiating arbitrary PHP objects with attacker-chosen properties that may enable code execution if suitable POP gadget chains exist.",
  "id": "GHSA-2vrr-cgr4-gfmm",
  "modified": "2026-09-17T18:31:46Z",
  "published": "2026-09-17T18:31:46Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-76834"
    },
    {
      "type": "WEB",
      "url": "https://github.com/b2evolution/b2evolution/commit/25c21cf9cc4261324001f9039509710b37ee2c4d"
    },
    {
      "type": "WEB",
      "url": "https://github.com/b2evolution/b2evolution/commit/335abf09bcea61717bd00bc1e3889f8100ebd1bb"
    },
    {
      "type": "WEB",
      "url": "https://github.com/b2evolution/b2evolution/commit/999b5ad1d59760d7e450ceb541f55432fc74cd27"
    },
    {
      "type": "WEB",
      "url": "https://b2evolution.net/news/2022/03/26/2022-update-eol"
    },
    {
      "type": "WEB",
      "url": "https://gist.github.com/axg11/3e29501c33f6e1e05ac2a00107afd64e"
    },
    {
      "type": "WEB",
      "url": "https://github.com/b2evolution/b2evolution"
    },
    {
      "type": "WEB",
      "url": "https://github.com/b2evolution/b2evolution/blob/7.2.5/htsrv/call_plugin.php#L49"
    },
    {
      "type": "WEB",
      "url": "https://github.com/b2evolution/b2evolution/blob/7.2.5/inc/_core/_param.funcs.php#L2860"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/b2evolution-cms-6.7.8-through-7.2.5-object-injection-via-negative-integer-array-key"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/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:N/SI:N/SA:N/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-2026-76834 (GCVE-0-2026-76834)

Vulnerability from cvelistv5 – Published: 2026-09-17 15:16 – Updated: 2026-09-17 15:16 Unsupported When Assigned

Title

b2evolution CMS 6.7.8 through 7.2.5 Object Injection via Negative Integer Array Key

Summary

Severity

9.2 (Critical)


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

8.1 (High)


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

CWE

CWE-502 - Deserialization of Untrusted Data

Assigner

VulnCheck mitre root

References

9 references

URL	Tags
https://gist.github.com/axg11/3e29501c33f6e1e05ac…	technical-description
https://github.com/b2evolution/b2evolution/blob/7…	technical-description
https://github.com/b2evolution/b2evolution/blob/7…	technical-description
https://github.com/b2evolution/b2evolution/commit…	patch
https://github.com/b2evolution/b2evolution/commit…	patch
https://github.com/b2evolution/b2evolution/commit…	technical-descriptionpatch
https://b2evolution.net/news/2022/03/26/2022-update-eol	vendor-advisory
https://github.com/b2evolution/b2evolution	product
https://www.vulncheck.com/advisories/b2evolution-…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
b2evolution	b2evolution CMS	Affected: 6.7.8 , ≤ 7.2.5 (semver) cpe:2.3:a:b2evolution:b2evolution_cms::::::::

Date Public

2026-07-31 00:00

Credits

Adrian Gaitan VulnCheck

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:github/b2evolution/b2evolution",
          "product": "b2evolution CMS",
          "repo": "https://github.com/b2evolution/b2evolution",
          "vendor": "b2evolution",
          "versions": [
            {
              "lessThanOrEqual": "7.2.5",
              "status": "affected",
              "version": "6.7.8",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:b2evolution:b2evolution_cms:*:*:*:*:*:*:*:*",
                  "versionEndIncluding": "7.2.5",
                  "versionStartIncluding": "6.7.8",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Adrian Gaitan"
        },
        {
          "lang": "en",
          "type": "coordinator",
          "value": "VulnCheck"
        }
      ],
      "datePublic": "2026-07-31T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "b2evolution CMS versions 6.7.8 through 7.2.5 contain an incomplete fix for CVE-2016-8901 where the serialized-array object check in param_check_serialized_array() fails to reject payloads with negative integer array keys. Unauthenticated attackers can submit crafted serialized PHP objects via POST requests to htsrv/call_plugin.php that bypass validation and reach unserialize(), instantiating arbitrary PHP objects with attacker-chosen properties that may enable code execution if suitable POP gadget chains exist."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 9.2,
            "baseSeverity": "CRITICAL",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          },
          "format": "CVSS"
        },
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 8.1,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-502",
              "description": "Deserialization of Untrusted Data",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-17T15:16:50.748Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://gist.github.com/axg11/3e29501c33f6e1e05ac2a00107afd64e"
        },
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://github.com/b2evolution/b2evolution/blob/7.2.5/inc/_core/_param.funcs.php#L2860"
        },
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://github.com/b2evolution/b2evolution/blob/7.2.5/htsrv/call_plugin.php#L49"
        },
        {
          "name": "Incomplete fix for CVE-2016-8901 (1 of 2)",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/b2evolution/b2evolution/commit/25c21cf9cc4261324001f9039509710b37ee2c4d"
        },
        {
          "name": "Incomplete fix for CVE-2016-8901 (2 of 2)",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/b2evolution/b2evolution/commit/999b5ad1d59760d7e450ceb541f55432fc74cd27"
        },
        {
          "name": "Introduces the flawed regular expression, first released in 6.7.8",
          "tags": [
            "technical-description",
            "patch"
          ],
          "url": "https://github.com/b2evolution/b2evolution/commit/335abf09bcea61717bd00bc1e3889f8100ebd1bb"
        },
        {
          "name": "b2evolution CMS end-of-life announcement",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://b2evolution.net/news/2022/03/26/2022-update-eol"
        },
        {
          "tags": [
            "product"
          ],
          "url": "https://github.com/b2evolution/b2evolution"
        },
        {
          "name": "VulnCheck Advisory: b2evolution CMS 6.7.8 through 7.2.5 Object Injection via Negative Integer Array Key",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/b2evolution-cms-6.7.8-through-7.2.5-object-injection-via-negative-integer-array-key"
        }
      ],
      "tags": [
        "unsupported-when-assigned"
      ],
      "title": "b2evolution CMS 6.7.8 through 7.2.5 Object Injection via Negative Integer Array Key",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-76834",
    "datePublished": "2026-09-17T15:16:50.748Z",
    "dateReserved": "2026-08-19T20:34:00.154Z",
    "dateUpdated": "2026-09-17T15:16:50.748Z",
    "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.

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.