How severe is CVE-2025-48203?

CVE-2025-48203 has a CVSS score of 5.5/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2025-48203?

CVE-2025-48203 affects the following packages: clickstorm/cs-seo (Packagist), clickstorm/cs-seo (Packagist), clickstorm/cs-seo (Packagist), clickstorm/cs-seo (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2025-48203?

Update clickstorm/cs-seo to 9.3.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-48203 is resolved across your whole dependency graph.

How do I detect CVE-2025-48203 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for clickstorm/cs-seo, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2025-48203 if there is no patch (or I can't update yet)?

Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Is CVE-2025-48203 actively exploited in the wild?

No public exploit code has been indexed for CVE-2025-48203 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2025-48203?

CVE-2025-48203 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 16th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2025-48203?

CVE-2025-48203 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2025-48203 published, and has it been updated?

CVE-2025-48203 was published on May 21, 2025 and was last updated on May 21, 2025. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘

🐘 Packagist

Not in CISA KEV

MEDIUM severity

CVE-2025-48203 — cs-seo

MEDIUMFix: clickstorm/cs_seo@1cf6c40

CVE-2025-48203 is a medium-severity (CVSS 5.5) Cross-site Scripting (XSS) vulnerability in clickstorm/cs-seo. A fix is available for clickstorm/cs-seo — see the affected versions and patch details below.

[clickstorm] SEO (cs_seo) TYPO3 extension Cross-site Scripting (XSS) vulnerability

Published

May 21, 2025

Updated

May 21, 2025

Affected

4 pkgs

Patched

4 / 4

Exploits

None indexed

Exploitation data as of Oct 30, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2025-48203.

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk+0.01%

Lower risk than most CVEs16th percentile — riskier than 16% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

4 pkgs affected

🐘clickstorm/cs-seo🐘clickstorm/cs-seo🐘clickstorm/cs-seo🐘clickstorm/cs-seo

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

Cross-site scripting (XSS) vulnerability in the [clickstorm] SEO (cs_seo) TYPO3 extension allows backend users to execute arbitrary script via the JSON-LD output.

Affected Packages

4 total 4 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`clickstorm/cs-seo`	≥ 9.0.0&&< 9.3.0	9.3.0`composer require clickstorm/cs-seo:^9.3.0`
🐘Packagist	`clickstorm/cs-seo`	≥ 8.0.0&&< 8.4.0	8.4.0`composer require clickstorm/cs-seo:^8.4.0`
🐘Packagist	`clickstorm/cs-seo`	≥ 7.0.0&&< 7.5.0	7.5.0`composer require clickstorm/cs-seo:^7.5.0`
🐘Packagist	`clickstorm/cs-seo`	≥ 6.3.0&&< 6.8.0	6.8.0`composer require clickstorm/cs-seo:^6.8.0`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for clickstorm/cs-seo, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update clickstorm/cs-seo to 9.3.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-48203 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Frequently Asked Questions

Cross-site scripting (XSS) vulnerability in the [clickstorm] SEO (cs_seo) TYPO3 extension allows backend users to execute arbitrary script via the JSON-LD output.

O3 Security · Impact-Aware SCA

Is CVE-2025-48203 in your dependencies?

Find it across Packagist, including transitive dependencies.

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CVSS Score

5.5/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Required

Scope

Unchanged

Confidentiality

Low

Integrity

Low

Availability

Low

Raw vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L/E:F/RL:O/RC:C

CWE Classification

CWE-79Cross-site Scripting (XSS)

Weaponization

No Nuclei template, Metasploit module or public proof-of-concept found.

Timeline

Disclosed

May 21, 2025

Identifiers

CVE-2025-48203

References

Advisorynvd.nist.gov · CVE 2025 48203 Webgithub.com · 1cf6c40821102b1f1508fe4e76825569340c8f90 Webgithub.com · CVE 2025 48203.yaml Webtypo3.org · typo3 ext sa 2025 005 Packagegithub.com · cs seo

Related vulnerabilities

Also affects clickstorm/cs-seo

This CVE is medium severity, in line with the other 1 CVE affecting clickstorm/cs-seo.

CVE-2025-30081

Same weakness: CWE-79

This CVE is medium severity; 5 of 7 other CVEs with CWE-79 are rated as high or higher (top: high).

CVE-2026-126075CVE-2026-126063CVE-2026-110802CVE-2026-123364CVE-2026-118670CVE-2026-88986CVE-2026-63197Browse all CWE-79

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedMay 21, 2025

CVE-2025-48203 — cs-seo

Exploitation Status

No confirmed exploitation observed yet

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Affected Packages

Detection & mitigation playbook

Detect

Fix

Workarounds

Frequently Asked Questions

Is CVE-2025-48203 in your dependencies?