CVE-2026-46556Public exploitNetwork attack vector

Authenticated internal service access via unrestricted avatar URL

Published Jul 21, 2026 · Updated Jul 21, 2026

Server-side request forgery in FlaskBB before 2.2.1 allows remote authenticated users to reach internal HTTP services through avatar URLs. The get_image_info function passes the user-supplied avatar URL directly to requests.get without validating its scheme, host, or IP address. Any account can trigger blind internal port scans and GET requests to private APIs or cloud metadata endpoints, while response differences expose network topology.

CVSS severity6.5
Medium
EPSS probability0.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Server-side request forgery in FlaskBB before 2.2.1 allows remote authenticated users to reach internal HTTP services through avatar URLs. The get_image_info function passes the user-supplied avatar URL directly to requests.get without validating its scheme, host, or IP address. Any account can trigger blind internal port scans and GET requests to private APIs or cloud metadata endpoints, while response differences expose network topology.

The record

CVE
CVE-2026-46556
Published
Jul 21, 2026
Updated
Jul 21, 2026
Vendor
FlaskBB
Product
FlaskBB
Classifications
CWE-918, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 21, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 21, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 2.2.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

FlaskBB · FlaskBBversion=< 2.2.1

Published CVSS scores

6.5GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-918Server-Side Request Forgery (SSRF)
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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