aio-libs aiohttp up to 3.14.1 WebSocket Client input validation

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability has been found in aio-libs aiohttp up to 3.14.1 and classified as problematic. Affected by this issue is some unknown functionality of the component WebSocket Client. Performing a manipulation results in input validation. This vulnerability is identified as CVE-2026-59881. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in aio-libs aiohttp up to 3.14.1. It has been classified as problematic. This affects an unknown part of the component WebSocket Client. The manipulation with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. This is going to have an impact on availability. The summary by CVE is:

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.2, the WebSocket client accepts and decompresses frames with the RSV1 bit set even when the permessage-deflate extension was not negotiated, allowing a malicious server to cause unexpected CPU and memory consumption. This issue is fixed in version 3.14.2.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-59881 since 07/07/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 331310 (Linux Distros Unpatched Vulnerability : CVE-2026-59881), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 3.14.2 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (331310) and EUVD (EUVD-2026-51257). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Input validation
CWE: CWE-20
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: 331310
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-59881

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: aiohttp 3.14.2

Timelineinfo

07/07/2026 CVE reserved
07/30/2026 +23 days Advisory disclosed
07/30/2026 +0 days VulDB entry created
08/03/2026 +4 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-59881 (🔒)
GCVE (CVE): GCVE-0-2026-59881
GCVE (VulDB): GCVE-100-384891
EUVD: 🔒

Entryinfo

Created: 07/30/2026 20:00
Updated: 08/03/2026 23:41
Changes: 07/30/2026 20:00 (55), 07/31/2026 13:56 (2), 08/03/2026 23:41 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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