High severity · published Jun 22, 2026
CVE-2026-54273
AIOHTTP: HTTP/1 Pipelined Requests Queue Without Limit
7.5
CVSS
0.5%
EPSS
No
On KEV
Description
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, no limit was present on the number of pipelined requests that could be queued. An attacker may be able to use pipelined requests to use excessive amounts of memory, potentially leading to DoS. This vulnerability is fixed in 3.14.1.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 42% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AI
aiohttp · aio-libs
< 3.14.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-54273
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-54273
Patch
https://github.com/aio-libs/aiohttp/commit/dfdfa9d5aad5d21f91c79fb2ceeba0f8046cb6cf
Third Party Advisory
https://github.com/aio-libs/aiohttp/security/advisories/GHSA-4fvr-rgm6-gqmc
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