PT-2026-29607 · Aiohttp+1 · Aiohttp+1

Uug4Na · CVE-2026-34518 · Published 2026-02-27 · Updated 2026-07-15

Positive Technologies (AI Summary)

CVSS v3.1

9.8

Critical

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions AIOHTTP versions prior to 3.13.4

Description When following redirects to a different origin, aiohttp removes the Authorization header while keeping the Cookie and Proxy-Authorization headers. This could lead to the leakage of sensitive information contained in the Cookie and Proxy-Authorization headers to an unintended party.

Recommendations Update to AIOHTTP version 3.13.4 or later.

Exploit

Fix

Information Disclosure

Weakness Enumeration

CWE-200

Related Identifiers

BDU:2026-09576

CLEANSTART-2026-AN27706

CLEANSTART-2026-AZ09261

CLEANSTART-2026-CQ05396

CLEANSTART-2026-FU07345

CLEANSTART-2026-KE11953

CLEANSTART-2026-MR94452

CLEANSTART-2026-NM83456

CLEANSTART-2026-QE89118

CLEANSTART-2026-SO50412

CLEANSTART-2026-WQ85001

CLEANSTART-2026-WU03167

CVE-2026-34518

ECHO-758D-EDBE-6881

GHSA-966J-VMVW-G2G9

OESA-2026-2192

OESA-2026-2193

OESA-2026-2194

OPENSUSE-SU-2026:21098-1

PYSEC-2026-2100

SUSE-SU-2026:22173-1

SUSE-SU-2026:3059-1

Affected Products

Aiohttp

Red Os

References · 317

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34518.json · Exploit
• https://github.com/aio-libs/aiohttp/commit/5351c980dcec7ad385730efdf4e1f4338b24fdb6 · Patch
• https://github.com/aio-libs/aiohttp/security/advisories/GHSA-966j-vmvw-g2g9 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-44307 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2024-52303 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-34513 · Security Note
• https://osv.dev/vulnerability/CLEANSTART-2026-CQ05396 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2025-69230 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-27448 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-34514 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-48525 · Security Note
• https://osv.dev/vulnerability/CVE-2026-34518 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-27205 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2025-69229 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-4539 · Security Note