Vulnerability-Lookup

FKIE_CVE-2026-85238

Vulnerability from fkie_nvd - Published: 2026-09-03 16:18 - Updated: 2026-09-03 16:45

Severity

7.6 (High) - CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

Summary

MISP contains a session fixation vulnerability in the CustomAuth authentication (a custom configuration) flow. When a user was successfully authenticated through CustomAuth, MISP stored the authenticated user identity in the existing session without first rotating the session identifier. As a result, if an attacker can cause a victim to use a session identifier known to the attacker before authentication, that same session identifier remains valid after the victim successfully authenticates. The attacker could subsequently reuse the fixed session identifier to access the victim's authenticated MISP session, potentially gaining the privileges associated with the victim's account. The issue occurs because __customAuthentication() wrote the authenticated user into the existing CakePHP session while the call to Session->renew() had previously been disabled. The patch restores session identifier rotation when a new authentication occurs or when the authenticated user changes, while avoiding unnecessary session renewal on every request.

References

	URL	Tags
	5a6e4751-2f3f-4070-9419-94fb35b644e8	https://github.com/MISP/MISP/commit/e2eb2f058

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "misp",
          "repo": "https://github.com/MISP/MISP/",
          "vendor": "misp",
          "versions": [
            {
              "lessThanOrEqual": "2.5.45",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "5a6e4751-2f3f-4070-9419-94fb35b644e8"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "MISP contains a session fixation vulnerability in the CustomAuth authentication (a custom configuration) flow. When a user was successfully authenticated through CustomAuth, MISP stored the authenticated user identity in the existing session without first rotating the session identifier.\n\n\nAs a result, if an attacker can cause a victim to use a session identifier known to the attacker before authentication, that same session identifier remains valid after the victim successfully authenticates. The attacker could subsequently reuse the fixed session identifier to access the victim\u0027s authenticated MISP session, potentially gaining the privileges associated with the victim\u0027s account.\n\n\nThe issue occurs because __customAuthentication() wrote the authenticated user into the existing CakePHP session while the call to Session-\u003erenew() had previously been disabled. The patch restores session identifier rotation when a new authentication occurs or when the authenticated user changes, while avoiding unnecessary session renewal on every request."
    }
  ],
  "id": "CVE-2026-85238",
  "lastModified": "2026-09-03T16:45:08.223",
  "metrics": {
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "HIGH",
          "attackRequirements": "PRESENT",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 7.6,
          "baseSeverity": "HIGH",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "LOW",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/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",
          "version": "4.0",
          "vulnAvailabilityImpact": "NONE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "5a6e4751-2f3f-4070-9419-94fb35b644e8",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-85238",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-03T15:43:07.468576Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-03T16:18:27.313",
  "references": [
    {
      "source": "5a6e4751-2f3f-4070-9419-94fb35b644e8",
      "url": "https://github.com/MISP/MISP/commit/e2eb2f058"
    }
  ],
  "sourceIdentifier": "5a6e4751-2f3f-4070-9419-94fb35b644e8",
  "vulnStatus": "Undergoing Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-384"
        }
      ],
      "source": "5a6e4751-2f3f-4070-9419-94fb35b644e8",
      "type": "Secondary"
    }
  ]
}

CVE-2026-85238 (GCVE-0-2026-85238)

Vulnerability from cvelistv5 – Published: 2026-09-03 15:30 – Updated: 2026-09-03 15:43

Title

Session Fixation in MISP CustomAuth Authentication Allows Session Hijacking

Summary

Severity

7.6 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-03 15:43 UTC

CWE

CWE-384 - Session Fixation

Assigner

CIRCL ENISA root

References

1 reference

URL	Tags
https://github.com/MISP/MISP/commit/e2eb2f058	patch

Impacted products

1 product

Vendor	Product	Version
misp	misp	Affected: 0 , ≤ 2.5.45 (semver)

Credits

Andras Iklody (the Insomniac MISP lead dev) Scottish Government - National Cyber Team Peter James

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-85238",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-03T15:43:07.468576Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-03T15:43:12.832Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "misp",
          "repo": "https://github.com/MISP/MISP/",
          "vendor": "misp",
          "versions": [
            {
              "lessThanOrEqual": "2.5.45",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "Andras Iklody"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Scottish Government - National Cyber Team"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Peter James"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
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              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eMISP contains a session fixation vulnerability in the \u003cstrong\u003eCustomAuth authentication (a custom configuration) flow\u003c/strong\u003e. When a user was successfully authenticated through CustomAuth, MISP stored the authenticated user identity in the existing session without first rotating the session identifier.\u003c/p\u003e\n\u003cp\u003eAs a result, if an attacker can cause a victim to use a session identifier known to the attacker before authentication, that same session identifier remains valid after the victim successfully authenticates. The attacker could subsequently reuse the fixed session identifier to access the victim\u0027s authenticated MISP session, potentially gaining the privileges associated with the victim\u0027s account.\u003c/p\u003e\n\u003cp\u003eThe issue occurs because \u003ccode\u003e__customAuthentication()\u003c/code\u003e wrote the authenticated user into the existing CakePHP session while the call to \u003ccode\u003eSession-\u0026gt;renew()\u003c/code\u003e had previously been disabled. The patch restores session identifier rotation when a \u003cstrong\u003enew authentication\u003c/strong\u003e occurs or when the authenticated user changes, while avoiding unnecessary session renewal on every request.\u003c/p\u003e\u003cbr\u003e"
            }
          ],
          "value": "MISP contains a session fixation vulnerability in the CustomAuth authentication (a custom configuration) flow. When a user was successfully authenticated through CustomAuth, MISP stored the authenticated user identity in the existing session without first rotating the session identifier.\n\n\nAs a result, if an attacker can cause a victim to use a session identifier known to the attacker before authentication, that same session identifier remains valid after the victim successfully authenticates. The attacker could subsequently reuse the fixed session identifier to access the victim\u0027s authenticated MISP session, potentially gaining the privileges associated with the victim\u0027s account.\n\n\nThe issue occurs because __customAuthentication() wrote the authenticated user into the existing CakePHP session while the call to Session-\u003erenew() had previously been disabled. The patch restores session identifier rotation when a new authentication occurs or when the authenticated user changes, while avoiding unnecessary session renewal on every request."
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-61",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-61 Session Fixation"
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
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            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "HIGH",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 7.6,
            "baseSeverity": "HIGH",
            "privilegesRequired": "LOW",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
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      "problemTypes": [
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          "descriptions": [
            {
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              "description": "CWE-384 Session Fixation",
              "lang": "en",
              "type": "CWE"
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      "providerMetadata": {
        "dateUpdated": "2026-09-03T15:30:42.478Z",
        "orgId": "5a6e4751-2f3f-4070-9419-94fb35b644e8",
        "shortName": "CIRCL"
      },
      "references": [
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/MISP/MISP/commit/e2eb2f058"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
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    "cveId": "CVE-2026-85238",
    "datePublished": "2026-09-03T15:30:42.478Z",
    "dateReserved": "2026-09-03T15:29:58.290Z",
    "dateUpdated": "2026-09-03T15:43:12.832Z",
    "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.

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FKIE_CVE-2026-85238

CVE-2026-85238 (GCVE-0-2026-85238)

Tags

Sightings

Nomenclature