CVE-2026-128125
AIOHTTP: Unbounded cookie storage in client CookieJar
Description
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.4, Set-Cookie parsing treats unrecognized name=value attributes as additional cookies, while CookieJar does not limit the number of cookies stored or sent. A malicious server can make an aiohttp client accumulate a very large cookie set, consume memory and CPU repeatedly across redirects, and construct an excessively large Cookie header for later requests to the same domain. This issue is fixed in version 3.14.4.
INFO
Published Date :
Nov. 13, 2026, 9:17 p.m.
Last Modified :
Nov. 13, 2026, 10:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update aiohttp to version 3.14.4 or later.
- Limit the number of cookies stored and sent.
- Validate cookie attributes during parsing.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-128125.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-128125 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-128125
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-128125 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-128125 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Nov. 13, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-128125', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-11-13T21:24:50.484299Z'} -
New CVE Received by [email protected]
Nov. 13, 2026
Action Type Old Value New Value Added Description AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.4, Set-Cookie parsing treats unrecognized name=value attributes as additional cookies, while CookieJar does not limit the number of cookies stored or sent. A malicious server can make an aiohttp client accumulate a very large cookie set, consume memory and CPU repeatedly across redirects, and construct an excessively large Cookie header for later requests to the same domain. This issue is fixed in version 3.14.4. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-1325 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/128xxx/CVE-2026-128125.json">CVE-2026-128125</a> Added Reference https://github.com/aio-libs/aiohttp/commit/6963ee0befec1502b6bb7b4db6c72d044c08f4fa Added Reference https://github.com/aio-libs/aiohttp/commit/b1f6c87b2bd3bd80f2b6c22ff46e11d00921e412 Added Reference https://github.com/aio-libs/aiohttp/pull/13930 Added Reference https://github.com/aio-libs/aiohttp/pull/13942 Added Reference https://github.com/aio-libs/aiohttp/releases/tag/v3.14.4 Added Reference https://github.com/aio-libs/aiohttp/security/advisories/GHSA-5pv8-vvhc-h7jv