Vulnerability-Lookup

CVE-2026-40597 (GCVE-0-2026-40597)

Vulnerability from cvelistv5 – Published: 2026-05-22 19:29 – Updated: 2026-05-26 19:06

Title

MantisBT has a Content Security Policy bypass via attachments

Summary

Mantis Bug Tracker (MantisBT) is an open source issue tracker. In versions 2.28.1 and below, given any pre-existing XSS / HTML injection vulnerability, an attacker can bypass the Content Security Policy's script-src directive by uploading a crafted attachment to any issue that, when accessed via the file_download.php link, will be downloaded with a valid JavaScript MIME type resulting in script execution. The uploaded payload must be sniffed as a valid JavaScript MIME type by PHP finfo (see file_create_finfo() API function). Non-JavaScript MIME types will not get imported in a <script> tag by the browser, due to response header X-Content-Type-Options being set to nosniff, which requires all imported JavaScript files to be a valid JavaScript MIME type. This issue has been fixed in version 2.28.2.

Severity

7.6 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-358 - Improperly Implemented Security Check for Standard

Assigner

GitHub_M

References

3 references

URL	Tags
https://github.com/mantisbt/mantisbt/security/adv…	x_refsource_CONFIRM
https://github.com/mantisbt/mantisbt/commit/9e3be…	x_refsource_MISC
https://mantisbt.org/bugs/view.php?id=37016	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
mantisbt	mantisbt	Affected: < 2.28.2

Show details on NVD website

JSON

To clipboard

{
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        "metrics": [
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                "id": "CVE-2026-40597",
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                "role": "CISA Coordinator",
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              "description": "CWE-358: Improperly Implemented Security Check for Standard",
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}

FKIE_CVE-2026-40597

Vulnerability from fkie_nvd - Published: 2026-05-22 20:16 - Updated: 2026-06-17 10:45

Severity

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

Summary

References

	URL	Tags
	security-advisories@github.com	https://github.com/mantisbt/mantisbt/commit/9e3bee2e7b909f4e3596985892b8bc8bee9e0bfe
	security-advisories@github.com	https://github.com/mantisbt/mantisbt/security/advisories/GHSA-9c3j-xm6v-j7j3
	security-advisories@github.com	https://mantisbt.org/bugs/view.php?id=37016

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "mantisbt",
          "vendor": "mantisbt",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 2.28.2"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Mantis Bug Tracker (MantisBT) is an open source issue tracker. In versions 2.28.1 and below, given any pre-existing XSS / HTML injection vulnerability, an attacker can bypass the Content Security Policy\u0027s script-src directive by uploading a crafted attachment to any issue that, when accessed via the file_download.php link, will be downloaded with a valid JavaScript MIME type resulting in script execution. The uploaded payload must be sniffed as a valid JavaScript MIME type by PHP finfo (see file_create_finfo() API function). Non-JavaScript MIME types will not get imported in a \u003cscript\u003e tag by the browser, due to response header X-Content-Type-Options being set to nosniff, which requires all imported JavaScript files to be a valid JavaScript MIME type. This issue has been fixed in version 2.28.2."
    }
  ],
  "id": "CVE-2026-40597",
  "lastModified": "2026-06-17T10:45:30.607",
  "metrics": {
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "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:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:L/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",
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          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
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    "ssvcV203": [
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        "ssvcData": {
          "id": "CVE-2026-40597",
          "options": [
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  "published": "2026-05-22T20:16:34.347",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/mantisbt/mantisbt/commit/9e3bee2e7b909f4e3596985892b8bc8bee9e0bfe"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/mantisbt/mantisbt/security/advisories/GHSA-9c3j-xm6v-j7j3"
    },
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      "url": "https://mantisbt.org/bugs/view.php?id=37016"
    }
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  "vulnStatus": "Deferred",
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        },
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        }
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      "type": "Secondary"
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}

GHSA-9C3J-XM6V-J7J3

Vulnerability from github – Published: 2026-05-11 19:34 – Updated: 2026-06-08 23:20

Summary

MantisBT has a Content Security Policy bypass via attachments

Details

Given any pre-existing XSS / HTML injection vulnerability, an attacker can bypass the Content Security Policy's script-src directive by uploading a crafted attachment to any issue that, when accessed via the file_download.php link, will be downloaded with a valid JavaScript MIME type resulting in script execution.

The uploaded payload must be sniffed as a valid JavaScript MIME type by PHP finfo (see file_create_finfo() API function). Non-JavaScript MIME types will not get imported in a <script> tag by the browser, due to response header X-Content-Type-Options being set to nosniff, which requires all imported JavaScript files to be a valid JavaScript MIME type.

Impact

Cross-site scripting

Patches

9e3bee2e7b909f4e3596985892b8bc8bee9e0bfe

Workarounds

None

Credits

Thanks to siunam (Tang Cheuk Hei) for discovering and responsibly reporting the issue.

Severity

7.6 (High)


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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 2.28.1"
      },
      "package": {
        "ecosystem": "Packagist",
        "name": "mantisbt/mantisbt"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.28.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-40597"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-358",
      "CWE-79"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-11T19:34:48Z",
    "nvd_published_at": "2026-05-22T20:16:34Z",
    "severity": "HIGH"
  },
  "details": "Given any pre-existing XSS / HTML injection vulnerability, an attacker can bypass the Content Security Policy\u0027s _script-src_ directive by uploading a crafted attachment to any issue that, when accessed via the _file_download.php_ link, will be downloaded with a valid JavaScript MIME type resulting in script execution.\n\nThe uploaded payload must be sniffed as a valid JavaScript MIME type by PHP finfo (see file_create_finfo() API function). Non-JavaScript MIME types will not get imported in a `\u003cscript\u003e` tag by the browser, due to response header X-Content-Type-Options being set to _nosniff_, which requires all imported JavaScript files to be a valid JavaScript MIME type.\n\n### Impact\nCross-site scripting\n\n### Patches\n- 9e3bee2e7b909f4e3596985892b8bc8bee9e0bfe\n\n### Workarounds\nNone\n\n### Credits\nThanks to siunam (Tang Cheuk Hei) for discovering and responsibly reporting the issue.",
  "id": "GHSA-9c3j-xm6v-j7j3",
  "modified": "2026-06-08T23:20:21Z",
  "published": "2026-05-11T19:34:48Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/mantisbt/mantisbt/security/advisories/GHSA-9c3j-xm6v-j7j3"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40597"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mantisbt/mantisbt/commit/9e3bee2e7b909f4e3596985892b8bc8bee9e0bfe"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/mantisbt/mantisbt"
    },
    {
      "type": "WEB",
      "url": "https://mantisbt.org/bugs/view.php?id=37016"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "MantisBT has a Content Security Policy bypass via attachments"
}

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.

Action not permitted

CVE-2026-40597 (GCVE-0-2026-40597)

FKIE_CVE-2026-40597

GHSA-9C3J-XM6V-J7J3

Impact

Patches

Workarounds

Credits

Tags

Sightings

Nomenclature