CVE-2026-34514

AIOHTTP: CRLF injection in multipart part content type header construction

At a glance

Severity: LOW 2.7
EPSS: EPSS 0.32 % · percentile 24 (2026-10-27)
State: PUBLISHED
Published: 2026-04-01
Updated: 2026-04-02
Assigner: GitHub_M
NVD status: Analyzed

Description

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an attacker who controls the content_type parameter in aiohttp could use this to inject extra headers or similar exploits. This issue has been patched in version 3.13.4.

Scores

Version	Score	Vector	Scored by
CVSS 4.0	LOW 2.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U	GitHub_M
CVSS 4.0	LOW 2.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/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	NVD · security-advisories@github.com (Secondary)
CVSS 3.1	MEDIUM 5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N	NVD · nvd@nist.gov (Primary)

Weaknesses (CWE)

CWE-113

Advisories

GHSA-2vrm-gr82-f7m5 — AIOHTTP has CRLF injection through multipart part content type header construction
PYSEC-2026-2096 — AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an attacker who controls the content_type parameter in

European references

ENISA EUVD · EUVD-2026-18037
GCVE · GCVE-0-2026-34514

CERT-FR advisories

CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2026-AVI-1094 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
CERTFR-2026-AVI-1056 — Multiples vulnérabilités dans les produits Splunk · cert.ssi.gouv.fr
CERTFR-2026-AVI-0556 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2026-AVI-0550 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr

Affected configurations (NVD CPE)

cpe:2.3:a:aiohttp:aiohttp:*:*:*:*:*:*:*:* < 3.13.4

Affected products

Product	Versions
aio-libs · aiohttp	affected < 3.13.4

References

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)	Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD