Medium severity · published Jan 5, 2026
CVE-2025-69225
AIOHTTP Regex Mismatch Allows Unicode in ASCII-Only Protocol Fields
5.3
CVSS
0.3%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 21% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AI
aiohttp · aio-libs
< 3.13.3 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-69225
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-69225
Patch
https://github.com/aio-libs/aiohttp/commit/c7b7a044f88c71cefda95ec75cdcfaa4792b3b96
Patch
https://github.com/aio-libs/aiohttp/security/advisories/GHSA-mqqc-3gqh-h2x8
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