What is CVE-2025-69225?

CVE-2025-69225 is a medium-severity vulnerability in Aiohttp, classified under Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling). CVSS score: 5.3/10. Published 2026-01-06.

How severe is CVE-2025-69225?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Aiohttp

CVE-2025-69225

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Versions 3.13.2 and below contain parser logic which allows non-ASCII decimals to be present in the Range header. There is no known impact, but there is the possibility that there's a method to exploit a request smuggling vulnerability. This issue is fixed in version 3.13.3.

Vulnerability class: HTTP Request Smuggling

Published 2026-01-06 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (18.0th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 18th percentile — 18.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000

Affected products

Aiohttp
Aio-Libs Aiohttp — versions < 3.13.3

Weakness classification (CWE)

CWE-444 — Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling)

References

github.com/aio-libs/aiohttp/security/advisories/GHSA-mqqc-3gqh-h2x8 (Patch, Vendor Advisory)
github.com/aio-libs/aiohttp/commit/c7b7a044f88c71cefda95ec75cdcfaa4792b3b96 (Patch)

Frequently asked questions

What is CVE-2025-69225?: CVE-2025-69225 is a medium-severity vulnerability in Aiohttp, classified under Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling). CVSS score: 5.3/10. Published 2026-01-06.
How severe is CVE-2025-69225?: Medium severity. CVSS v3 base score is 5.3 out of 10.