aio-libs aiohttp up to 3.12.13 Python Parser request smuggling

CVSS Meta Temp Score
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CTI Interest Score
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7.2$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in aio-libs aiohttp up to 3.12.13. The impacted element is an unknown function of the component Python Parser. The manipulation leads to request smuggling. This vulnerability is uniquely identified as CVE-2025-53643. The attack is possible to be carried out remotely. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in aio-libs aiohttp up to 3.12.13. It has been rated as critical. This issue affects some unknown functionality of the component Python Parser. The manipulation with an unknown input leads to a request smuggling vulnerability. Using CWE to declare the problem leads to CWE-444. The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.12.14, the Python parser is vulnerable to a request smuggling vulnerability due to not parsing trailer sections of an HTTP request. If a pure Python version of aiohttp is installed (i.e. without the usual C extensions) or AIOHTTP_NO_EXTENSIONS is enabled, then an attacker may be able to execute a request smuggling attack to bypass certain firewalls or proxy protections. Version 3.12.14 contains a patch for this issue.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2025-53643 since 07/07/2025. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 242322 (aioHTTP < 3.12.14 Request Smuggling (CVE-2025-53643)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 3.12.14 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (242322), EUVD (EUVD-2025-21384) and CERT Bund (WID-SEC-2025-2798). Be aware that VulDB is the high quality source for vulnerability data.

Affected

  • Red Hat Enterprise Linux
  • Red Hat OpenShift
  • IBM App Connect Enterprise

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 7.4
VulDB Meta Temp Score: 7.2

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Request smuggling
CWE: CWE-444
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 242322
Nessus Name: aioHTTP < 3.12.14 Request Smuggling (CVE-2025-53643)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: aiohttp 3.12.14

Timelineinfo

07/07/2025 CVE reserved
07/14/2025 +7 days Advisory disclosed
07/14/2025 +0 days VulDB entry created
01/10/2026 +180 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2025-53643 (🔒)
GCVE (CVE): GCVE-0-2025-53643
GCVE (VulDB): GCVE-100-316367
EUVD: 🔒
CERT Bund: WID-SEC-2025-2798 - Red Hat OpenShift Service Mesh: Mehrere Schwachstellen

Entryinfo

Created: 07/14/2025 23:08
Updated: 01/10/2026 02:34
Changes: 07/14/2025 23:08 (67), 07/15/2025 01:16 (1), 07/19/2025 15:26 (2), 08/14/2025 23:23 (13), 01/10/2026 02:34 (8)
Complete: 🔍
Cache ID: 216::103

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