UBUNTU-CVE-2026-82209
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UBUNTU-CVE-2026-82209
Summary:
Details: 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`).
References: https://ubuntu.com/security/CVE-2026-82209, https://www.cve.org/CVERecord?id=CVE-2026-82209, https://curl.se/docs/CVE-2026-82209.html, https://github.com/curl/curl/commit/95c1e8915dce64606bd753fd47f, https://ubuntu.com/security/notices/USN-8820-1
Affected packages
Package
Name: curl
Purl: pkg:deb/ubuntu/curl?arch=source&distro=esm-infra%2Fbionic
Affected ranges
Type: ECOSYSTEM
Events:
