Cyber Resilience

CVE-2026-54278

Aiohttp ≤ 3.14.1

Published
22 June 2026
Modified
26 June 2026
Patch / advisory
CVSS Score v4 6.6
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/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
EPSS Score 0.0040 32th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-54278 is a medium-severity Data Amplification (CWE-409) vulnerability in Aiohttp Aiohttp. Its CVSS base score is 6.6 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 32th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SC-5 (Denial-of-service Protection) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, during cleanup it is possible for a compressed request body to be decompressed into memory in one chunk. An attacker may be able to send a…

more

compressed payload in specific situations that could be decompressed into memory, potentially leading to DoS (a zip bomb edge case). This vulnerability is fixed in 3.14.1.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
Why these techniques?

Vulnerability enables remote DoS via malicious compressed payload (zip bomb) against public-facing AIOHTTP server, mapping to application exploitation for endpoint DoS.

Confidence: MEDIUM · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2025-69229Same product: Aiohttp Aiohttp
CVE-2026-34513Same product: Aiohttp Aiohttp
CVE-2026-22815Same product: Aiohttp Aiohttp
CVE-2026-54280Same product: Aiohttp Aiohttp
CVE-2026-34516Same product: Aiohttp Aiohttp
CVE-2026-54277Same product: Aiohttp Aiohttp
CVE-2025-69223Same product: Aiohttp Aiohttp
CVE-2026-34517Same product: Aiohttp Aiohttp
CVE-2025-69228Same product: Aiohttp Aiohttp
CVE-2026-54274Same product: Aiohttp Aiohttp

Affected Assets

aiohttp
aiohttp
≤ 3.14.1

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-10 Information Input Validation
  • SC-5 Denial-of-service Protection
Detect
Catch it (NIST detect / respond)
  • SI-4 System Monitoring
Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly requires validation and size limits on information inputs, preventing uncontrolled decompression of compressed request bodies into memory.

prevent

Explicitly protects against denial-of-service via resource exhaustion from malicious compressed payloads (zip-bomb edge case).

detect

Enables monitoring of memory and resource consumption anomalies that would result from a successful decompression attack.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure-development practices include input-validation and resource-limit checks that prevent improper handling of compressed data.

DE.CM-09 partial match
prevents

Runtime monitoring of compute resources can detect exhaustion caused by decompression bombs.

PR.IR-04 partial match
prevents

Capacity planning and monitoring directly limits the availability impact of data-amplification attacks.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Security testing can uncover decompression-bomb vulnerabilities before release.

mitigates

Redundancy helps availability but does not address the root cause of the weakness.

detects

Monitoring can detect anomalous resource usage but does not prevent the weakness.

prevents

Secure development lifecycle includes input validation and resource-limit checks that mitigate data-amplification attacks.

prevents

Application security requirements can mandate limits on decompression size and ratio.

prevents

Secure architecture principles encourage defensive design against resource-exhaustion threats.

References