CVE-2025-53528 json
Cadwyn is vulnerable to an XSS attack through its docs page
published last yr. modified 4mo ago also GHSA-2gxp-6r36-m97r , PYSEC-2025-71 , EUVD-2025-22154
- cvss
- 7.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 20%
- public exploits
- 0
- none known
Summary
Cadwyn creates production-ready community-driven modern Stripe-like API versioning in FastAPI. In versions before 5.4.3, the version parameter of the "/docs" endpoint is vulnerable to a Reflected XSS (Cross-Site Scripting) attack. This XSS would notably allow an attacker to execute JavaScript code on a user's session for any application based on Cadwyn via a one-click attack. The vulnerability has been fixed in version 5.4.3.
Patch / fix
Is CVE-2025-53528 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- last yr.
Exploit prediction
0.28% chance of exploitation in the next 30 days, higher than 20% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:L |
| GitHub | 3.1 | 7.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:L |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | cadwyn | <5.4.3 |
5.4.3 |
Affected products
- zmievsa cadwyn
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/zmievsa/cadwyn/commit/b424ecd57cd8dabbc8fe39b8f8ccafea629c7728
web, patch
-
github.com
/zmievsa/cadwyn/security/advisories/GHSA-2gxp-6r36-m97r
web, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2025-53528
advisory
-
github.com
/pypa/advisory-database/tree/main/vulns/cadwyn/PYSEC-2025-71.yaml
web
-
github.com
/zmievsa/cadwyn
package
-
github.com
/zmievsa/cadwyn/blob/5.4.3/CHANGELOG.md#543
web
Sources
- CVE List CVE-2025-53528
- GitHub Advisory GHSA-2gxp-6r36-m97r
- NVD CVE-2025-53528
- OSV PYSEC-2025-71
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.