Vulnerability-Lookup

GHSA-VCM5-GVMP-78MP

Vulnerability from github – Published: 2026-06-23 17:02 – Updated: 2026-07-21 13:35

Summary

Gogs has DOM-based XSS via Milestone Name on New Issue Page

Details

Summary

The fix for GHSA-vgjm-2cpf-4g7c (DOM-based XSS via milestone selection) was only applied to templates/repo/issue/view_content.tmpl but not to templates/repo/issue/new_form.tmpl. An attacker can store an HTML/JavaScript payload in a milestone name, and when any user opens the New Issue page and interacts with the milestone dropdown, the payload executes in their browser via Semantic UI's preserveHTML behavior.

Details

GHSA-vgjm-2cpf-4g7c was patched by adding | Sanitize (bluemonday HTML tag stripping) to milestone name rendering in view_content.tmpl. However, the same milestone dropdown exists in new_form.tmpl and was not patched.

In new_form.tmpl, milestone names are rendered with Go's default auto-escaping ({{.Name}}), which converts < to < etc. This prevents direct HTML injection. However, when the browser renders the DOM, the text content of the element contains the decoded original payload (e.g., <img src=x onerror=alert(1)>).

Semantic UI 2.4.2's dropdown component has preserveHTML: true as the default setting. When a user selects a dropdown item, the internal set.text() method calls jQuery's .html() with the item's text content. This re-parses the decoded text as HTML, creating the injected element and triggering the JavaScript event handler.

PoC

poc.zip Please extract the uploaded compressed file before proceeding

docker compose up --build

스크린샷 2026-04-06 오후 9 34 05

Impact

Stored DOM XSS: Any user with write access to a repository can create a malicious milestone. Any other user who visits the New Issue page and interacts with the milestone dropdown will have arbitrary JavaScript executed in their browser session.
Session hijacking: The attacker can steal session cookies, perform actions as the victim, or escalate privileges.

Severity

4.8 (Medium)


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

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JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "gogs.io/gogs"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.14.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-52807"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-23T17:02:52Z",
    "nvd_published_at": "2026-06-24T21:16:56Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\nThe fix for GHSA-vgjm-2cpf-4g7c (DOM-based XSS via milestone selection) was only applied to `templates/repo/issue/view_content.tmpl` but not to `templates/repo/issue/new_form.tmpl`. An attacker can store an HTML/JavaScript payload in a milestone name, and when any user opens the New Issue page and interacts with the milestone dropdown, the payload executes in their browser via Semantic UI\u0027s `preserveHTML` behavior.\n\n### Details\nGHSA-vgjm-2cpf-4g7c was patched by adding `| Sanitize` (bluemonday HTML tag stripping) to milestone name rendering in `view_content.tmpl`. However, the same milestone dropdown exists in `new_form.tmpl` and was **not** patched.\n\nIn `new_form.tmpl`, milestone names are rendered with Go\u0027s default auto-escaping (`{{.Name}}`), which converts `\u003c` to `\u0026lt;` etc. This prevents direct HTML injection. However, when the browser renders the DOM, the text content of the element contains the **decoded** original payload (e.g., `\u003cimg src=x onerror=alert(1)\u003e`).\n\nSemantic UI 2.4.2\u0027s dropdown component has `preserveHTML: true` as the default setting. When a user selects a dropdown item, the internal `set.text()` method calls jQuery\u0027s `.html()` with the item\u0027s text content. This re-parses the decoded text as HTML, creating the injected element and triggering the JavaScript event handler.\n\n### PoC\n[poc.zip](https://github.com/user-attachments/files/26508268/poc.zip)\nPlease extract the uploaded compressed file before proceeding\n\n1. docker compose up --build\n\n\u003cimg width=\"1325\" height=\"315\" alt=\"\u1109\u1173\u110f\u1173\u1105\u1175\u11ab\u1109\u1163\u11ba 2026-04-06 \u110b\u1169\u1112\u116e 9 34 05\" src=\"https://github.com/user-attachments/assets/87895cce-5b8e-4320-829a-87a5890cc0d9\" /\u003e\n\n### Impact\n- Stored DOM XSS: Any user with write access to a repository can create a malicious milestone. Any other user who visits the New Issue page and interacts with the milestone dropdown will have arbitrary JavaScript executed in their browser session.\n- Session hijacking: The attacker can steal session cookies, perform actions as the victim, or escalate privileges.",
  "id": "GHSA-vcm5-gvmp-78mp",
  "modified": "2026-07-21T13:35:37Z",
  "published": "2026-06-23T17:02:52Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/gogs/gogs/security/advisories/GHSA-vcm5-gvmp-78mp"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-52807"
    },
    {
      "type": "WEB",
      "url": "https://github.com/gogs/gogs/pull/8325"
    },
    {
      "type": "WEB",
      "url": "https://github.com/gogs/gogs/commit/573eacdc658641487f8ad883da96b29ec8e2852d"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/gogs/gogs"
    },
    {
      "type": "WEB",
      "url": "https://github.com/gogs/gogs/releases/tag/v0.14.3"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/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"
    }
  ],
  "summary": "Gogs has DOM-based XSS via Milestone Name on New Issue Page"
}

CVE-2026-52807 (GCVE-0-2026-52807)

Vulnerability from cvelistv5 – Published: 2026-06-24 20:25 – Updated: 2026-06-25 15:37

Title

Gogs: DOM-based XSS via Milestone Name on New Issue Page

Summary

Gogs is an open source self-hosted Git service. Prior to 0.14.3, in new_form.tmpl, milestone names are rendered with Go's default auto-escaping ({{.Name}}), which converts < to < etc. This prevents direct HTML injection. However, when the browser renders the DOM, the text content of the element contains the decoded original payload. Semantic UI 2.4.2's dropdown component has preserveHTML: true as the default setting. When a user selects a dropdown item, the internal set.text() method calls jQuery's .html() with the item's text content. This re-parses the decoded text as HTML, creating the injected element and triggering the JavaScript event handler. An attacker can store an HTML/JavaScript payload in a milestone name, and when any user opens the New Issue page and interacts with the milestone dropdown, the payload executes in their browser via Semantic UI's preserveHTML behavior. This vulnerability is fixed in 0.14.3.

Severity

4.8 (Medium)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-25 15:37 UTC

CWE

CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Assigner

GitHub_M mitre root

References

4 references

URL	Tags
https://github.com/gogs/gogs/security/advisories/…	x_refsource_CONFIRM
https://github.com/gogs/gogs/pull/8325	x_refsource_MISC
https://github.com/gogs/gogs/commit/573eacdc65864…	x_refsource_MISC
https://github.com/gogs/gogs/releases/tag/v0.14.3	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
gogs	gogs	Affected: < 0.14.3

Show details on NVD website

JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-52807",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-25T15:37:32.952801Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-25T15:37:35.956Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/gogs/gogs/security/advisories/GHSA-vcm5-gvmp-78mp"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "gogs",
          "vendor": "gogs",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.14.3"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Gogs is an open source self-hosted Git service. Prior to 0.14.3, in new_form.tmpl, milestone names are rendered with Go\u0027s default auto-escaping ({{.Name}}), which converts \u003c to \u0026lt; etc. This prevents direct HTML injection. However, when the browser renders the DOM, the text content of the element contains the decoded original payload. Semantic UI 2.4.2\u0027s dropdown component has preserveHTML: true as the default setting. When a user selects a dropdown item, the internal set.text() method calls jQuery\u0027s .html() with the item\u0027s text content. This re-parses the decoded text as HTML, creating the injected element and triggering the JavaScript event handler. An attacker can store an HTML/JavaScript payload in a milestone name, and when any user opens the New Issue page and interacts with the milestone dropdown, the payload executes in their browser via Semantic UI\u0027s preserveHTML behavior. This vulnerability is fixed in 0.14.3."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 4.8,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "LOW",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "LOW",
            "subIntegrityImpact": "LOW",
            "userInteraction": "ACTIVE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-79",
              "description": "CWE-79: Improper Neutralization of Input During Web Page Generation (\u0027Cross-site Scripting\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-24T20:25:49.230Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/gogs/gogs/security/advisories/GHSA-vcm5-gvmp-78mp",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/gogs/gogs/security/advisories/GHSA-vcm5-gvmp-78mp"
        },
        {
          "name": "https://github.com/gogs/gogs/pull/8325",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/gogs/gogs/pull/8325"
        },
        {
          "name": "https://github.com/gogs/gogs/commit/573eacdc658641487f8ad883da96b29ec8e2852d",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/gogs/gogs/commit/573eacdc658641487f8ad883da96b29ec8e2852d"
        },
        {
          "name": "https://github.com/gogs/gogs/releases/tag/v0.14.3",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/gogs/gogs/releases/tag/v0.14.3"
        }
      ],
      "source": {
        "advisory": "GHSA-vcm5-gvmp-78mp",
        "discovery": "UNKNOWN"
      },
      "title": "Gogs: DOM-based XSS via Milestone Name on New Issue Page"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-52807",
    "datePublished": "2026-06-24T20:25:49.230Z",
    "dateReserved": "2026-06-08T18:02:19.731Z",
    "dateUpdated": "2026-06-25T15:37:35.956Z",
    "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.

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.

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Action not permitted

GHSA-VCM5-GVMP-78MP

Summary

Details

PoC

Impact

CVE-2026-52807 (GCVE-0-2026-52807)

Tags

Sightings

Nomenclature

Related by attack behaviour