Vulnerabilities in pkg:pypi/flaskbb

PACKAGE
Advisory Identifier: GHSA-xq32-9g7q-7297
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Advisory Summary

CVE-2026-46556 is a MODERATE (CVSS 6.5) ssrf vulnerability (CWE-918: Server-Side Request Forgery (SSRF)) affecting FlaskBB libraries in the PyPI ecosystem. The issue involves ssrf in get_image_info() via unrestricted avatar url. Remediation is available in the latest vendor maintenance releases.

1 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:pypi/flaskbb

1 Known Advisory Record(s)

Vulnerability advisories affecting package pkg:pypi/flaskbb. Select an advisory below to view technical details or fixes.

Advisory ID CVE / NVD Severity Summary
GHSA-xq32-9g7q-7297 CVE-2026-46556 MODERATE FlaskBB: SSRF in get_image_info() via unrestricted avatar URL

CVE-2026-46556 at a Glance

CVE Identifier CVE-2026-46556
GHSA Identifier GHSA-xq32-9g7q-7297
Severity MODERATE
CVSS v3.1 Base Score 6.5
CWE Classification CWE-918: Server-Side Request Forgery (SSRF)
Affected Product FlaskBB
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 6.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2026-46556

To remediate this vulnerability, upgrade all affected FlaskBB dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

flaskbb fixed: Latest secure release 
pip install flaskbb>=Latest secure release
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

pip show flaskbb

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2026-46556, inspect your installed packages using pip:

pip show flaskbb

Analyze the terminal output to locate any version of FlaskBB in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: The pip show flaskbb command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-918: Server-Side Request Forgery (SSRF), where the web server receives a url or similar request from an upstream component and retrieves the contents of this url, but it does not sufficiently ensure that the request is being sent to the expected destination. In FlaskBB, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

###Summary A Server-Side Request Forgery (SSRF) vulnerability in get_image_info() allows any authenticated user to force the server to send HTTP requests to arbitrary internal endpoints, including cloud metadata services (e.g., AWS 169.254.169.254). This is a blind SSRF with confirmed internal port scanning and internal API triggering capabilities. CVSS 6.5 Medium. ###Details In flaskbb/utils/helpers.py (line 571), the url parameter is passed directly to requests.get(url, stream=True) without any validation of scheme, host, or IP address. ``` python# flaskbb/utils/helpers.py:571 def get_image_info(url: str): r = requests.get(url, timeout=(3.05, 27), stream=True) ``` Attack chain: ``` POST /user/settings/user-details (avatar URL) → ValidateAvatarURL.validate() # validators.py:103 → check_image(avatar) # helpers.py:628 → get_image_info(url) # helpers.py:571 → requests.get(url) # No domain/IP restriction Entry points: /user/settings/user-details (any authenticated user) /admin/users/<id>/edit (admin only) ``` ###PoC [submit.zip](https://github.com/user-attachments/files/26301527/submit.zip) Log in to FlaskBB as any user Navigate to Settings → User Details Enter http://169.254.169.254/latest/meta-data/ as the avatar URL Submit the form The server sends a GET request to the internal metadata endpoint Three exploitation channels confirmed: Server-side request: Captured on mock metadata server Internal port scan: check_image() returns distinct errors (CONN_REFUSED, NO_CONTENT_LENGTH, TYPE_NOT_ALLOWED, SUCCESS) that map internal network topology Internal API triggering: Mock APIs on 127.0.0.1:9200 triggered via SSRF (deploy, shutdown, key dump endpoints) ###Impact Any authenticated user is impacted. Attackers can force the server to request internal services, cloud metadata endpoints, or private network resources. On cloud deployments (AWS/GCP/Azure), IAM credentials can be leaked. In production, any GET-triggered internal service is reachable: CI/CD webhooks, Elasticsearch, etcd, Consul, etc.

CVE-2026-46556 Affected FlaskBB Versions

1 component(s)
Product / Package Ecosystem Affected Versions Fixed Version
flaskbb
pypi/flaskbb
PyPI
≤ 2.2.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/flaskbb/flaskbb/security/advisories/GHSA-xq32-9g7q-7297
FlaskBB Source Repository REPOSITORY
https://github.com/flaskbb/flaskbb

Frequently Asked Questions

What is CVE-2026-46556?
CVE-2026-46556 is a security vulnerability in FlaskBB involving SSRF in get_image_info() via unrestricted avatar URL under CWE-918: Server-Side Request Forgery (SSRF).
Which FlaskBB versions are affected?
Affected versions include releases prior to current release patches across affected packages: flaskbb.
What version fixes CVE-2026-46556?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
Is flaskbb affected?
Yes, flaskbb is affected in releases prior to Latest secure release. Upgrade your dependency to Latest secure release or later.
What is the CVSS score of CVE-2026-46556?
CVE-2026-46556 has a CVSS v3.1 base score of 6.5 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2026-46556?
CVE-2026-46556 is classified under CWE-918: Server-Side Request Forgery (SSRF) (The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.).
How can I check PyPI dependencies for CVE-2026-46556?
Run the dependency tree command: 'pip show flaskbb'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-xq32-9g7q-7297",
  "modified" : "2026-05-21T20:42:09Z",
  "published" : "2026-05-21T20:42:09Z",
  "aliases" : [ "CVE-2026-46556" ],
  "summary" : "FlaskBB: SSRF in get_image_info() via unrestricted avatar URL",
  "details" : "###Summary\nA Server-Side Request Forgery (SSRF) vulnerability in get_image_info() allows any authenticated user to force the server to send HTTP requests to arbitrary internal endpoints, including cloud metadata services (e.g., AWS 169.254.169.254). This is a blind SSRF with confirmed internal port scanning and internal API triggering capabilities. CVSS 6.5 Medium.\n\n###Details\nIn flaskbb/utils/helpers.py (line 571), the url parameter is passed directly to requests.get(url, stream=True) without any validation of scheme, host, or IP address.\n```\npython# flaskbb/utils/helpers.py:571\ndef get_image_info(url: str):\n    r = requests.get(url, timeout=(3.05, 27), stream=True)\n```\n\nAttack chain:\n\n```\nPOST /user/settings/user-details (avatar URL)\n→ ValidateAvatarURL.validate()    # validators.py:103\n→ check_image(avatar)             # helpers.py:628\n→ get_image_info(url)             # helpers.py:571\n→ requests.get(url)               # No domain/IP restriction\nEntry points:\n\n/user/settings/user-details (any authenticated user)\n/admin/users/<id>/edit (admin only)\n\n```\n\n###PoC\n[submit.zip](https://github.com/user-attachments/files/26301527/submit.zip)\n\nLog in to FlaskBB as any user\nNavigate to Settings → User Details\nEnter http://169.254.169.254/latest/meta-data/ as the avatar URL\nSubmit the form\nThe server sends a GET request to the internal metadata endpoint\n\nThree exploitation channels confirmed:\n\nServer-side request: Captured on mock metadata server\nInternal port scan: check_image() returns distinct errors (CONN_REFUSED, NO_CONTENT_LENGTH, TYPE_NOT_ALLOWED, SUCCESS) that map internal network topology\nInternal API triggering: Mock APIs on 127.0.0.1:9200 triggered via SSRF (deploy, shutdown, key dump endpoints)\n\n###Impact\nAny authenticated user is impacted. Attackers can force the server to request internal services, cloud metadata endpoints, or private network resources. On cloud deployments (AWS/GCP/Azure), IAM credentials can be leaked. In production, any GET-triggered internal service is reachable: CI/CD webhooks, Elasticsearch, etcd, Consul, etc.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "flaskbb"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "2.2.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/flaskbb/flaskbb/security/advisories/GHSA-xq32-9g7q-7297"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/flaskbb/flaskbb"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-918" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-21T20:42:09Z",
    "nvd_published_at" : null
  }
}