CVE-2026-82209

Published Sep 6, 2026

Last updated 6 days ago

Overview

Description
When libpsl support is enabled, libcurl fails to enforce the Public Suffix List boundary check when processing a `Set-Cookie` header where the `Domain` attribute explicitly matches an origin host that is itself a public suffix (e.g., `Domain=co.uk` set by `co.uk`). Instead of coercing it into a strict host-only cookie, libcurl saves the cookie with wildcard domain scope (`.co.uk`). Consequently, the cookie is inappropriately included in subsequent outbound requests or HTTP redirects to arbitrary sibling subdomains under the same public suffix (e.g., `attacker.co.uk`).
Source
2499f714-1537-4658-8207-48ae4bb9eae9
NVD status
Modified
Products
curl

Risk scores

CVSS 3.1

Type
Secondary
Base score
8.2
Impact score
4.2
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N
Severity
HIGH

Weaknesses

2499f714-1537-4658-8207-48ae4bb9eae9
CWE-201
134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-201

Social media

Hype score
Not currently trending

Configurations