CVE-2025-55735Public exploitNetwork attack vector

Stored XSS via unescaped post content

Published Aug 19, 2025 · Updated Aug 19, 2025

Stored XSS in Dogukan Urker FlaskBlog 2.8.0 and earlier allows remote attackers to run scripts in readers' browsers via crafted posts. The post creation path stores unvalidated postContent, and template/routes.html renders it through Jinja's safe filter instead of escaping HTML. Execution requires a reader to load the stored post, exposing browser-accessible data and actions within that reader's FlaskBlog session.

CVSS severity5.3
Medium
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Dogukan Urker FlaskBlog 2.8.0 and earlier allows remote attackers to run scripts in readers' browsers via crafted posts. The post creation path stores unvalidated postContent, and template/routes.html renders it through Jinja's safe filter instead of escaping HTML. Execution requires a reader to load the stored post, exposing browser-accessible data and actions within that reader's FlaskBlog session.

The record

CVE
CVE-2025-55735
Published
Aug 19, 2025
Updated
Aug 19, 2025
Vendor
Dogukan Urker
Product
FlaskBlog
Classifications
CWE-807, CWE-79, T1059.007
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 19, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 19, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=<= 2.8.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Dogukan Urker · FlaskBlogversion=<= 2.8.0

Published CVSS scores

5.3GitHub Security AdvisoriesCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA: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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-807Reliance on Untrusted Inputs in a Security Decision
CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007JavaScript/JScript

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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