CVE-2026-82209

published 2026-09-06

CVE-2026-82209: When libpsl support is enabled, libcurl fails to enforce the Public Suffix List boundary check when processing a `Set-Cookie` header where the `Domain`…

Priority P3 50 high 8.2 CVSS 3.1

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

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`).

Affected

104 ranges · showing 25

Vendor	Product	Version range	Fixed in
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—
curl	curl	—	—

CVSS provenance

nvd v3.1 8.2 HIGH CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N

vendor_redhat 8.2 HIGH

vendor_ubuntu 7.4 HIGH

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CWE-201 CWE-501