Is CVE-2026-54274 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-54274 being exploited in the wild.

How severe is CVE-2026-54274?

Medium severity, with a CVSS score of 4, published 22 June 2026.

Which products and versions are affected?

aiohttp (PyPI) <= 3.14.0, ECOSYSTEM:introduced=0,fixed=3.14.1.

Is there a fix for CVE-2026-54274?

Yes. aiohttp (PyPI): upgrade to 3.14.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-54274 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-54274?

Check whether you run aiohttp (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-54274: aio-libs aiohttp memory exhaustion in WebSocket handler

Q: Which products and versions are affected?

aiohttp (PyPI) <= 3.14.0, ECOSYSTEM:introduced=0,fixed=3.14.1.

Q: Is there a fix for CVE-2026-54274?

Yes. aiohttp (PyPI): upgrade to 3.14.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-54274 attacked?

It is attacked over the network, in a software library.

Q: Am I affected by CVE-2026-54274?

Check whether you run aiohttp (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-54274 · Severity: medium · CVSS 4 · Published 2026-06-22

AIOHTTP is a popular Python library used to build web servers and clients. A vulnerability in how it handles WebSocket connections allows an attacker to bypass memory safety limits by sending incomplete data packets. This can lead to a denial-of-service (DoS) condition where the server crashes or becomes unresponsive due to excessive memory consumption.

Technologies: aiohttp (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-54274 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-54274 being exploited in the wild.
How severe is CVE-2026-54274?: Medium severity, with a CVSS score of 4, published 22 June 2026.
Which products and versions are affected?: aiohttp (PyPI) <= 3.14.0, ECOSYSTEM:introduced=0,fixed=3.14.1.
Is there a fix for CVE-2026-54274?: Yes. aiohttp (PyPI): upgrade to 3.14.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-54274 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-54274?: Check whether you run aiohttp (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

aiohttp (PyPI): upgrade to 3.14.1 or later
```
pip install "aiohttp>=3.14.1"
```

Technical details

A resource exhaustion vulnerability (CWE-770) exists in AIOHTTP's WebSocket implementation. The root cause is a failure to strictly enforce memory usage limits when processing large, incomplete WebSocket frame payloads. An unauthenticated remote attacker can exploit this by initiating a WebSocket connection and sending specially crafted incomplete frames, causing the server to allocate memory beyond configured thresholds. This can lead to a Denial of Service (DoS) via memory exhaustion. The issue is resolved in version 3.14.1 by improving WebSocket frame validation and check mechanisms.

Affected products

aio-libs aiohttp < 3.14.1

Identifiers

CVE-2026-54274
GHSA-xcgm-r5h9-7989
PYSEC-2026-2108

Timeline

2026-06-08: advisory: GitHub Security Advisory published
2026-06-22: disclosed: NVD publication date
2026-06-22: patched: Fix released in version 3.14.1

References

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