HIGHVulnerability

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` 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`).

Properties

severity
HIGH
score
8.2
cve_id
CVE-2026-82209
signal_observed_at
2026-09-16T21:37:07+00:00
vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N
published_at
2026-09-06T18:17:22.847
last_modified
2026-09-15T07:16:31.233

Related Entities (3)

AFFECTS_PRODUCT (1)

[Product]

DESCRIBED_BY (1)

[Source]NVD

HAS_WEAKNESS (1)

[Weakness]Insertion of Sensitive Information Into Sent Data

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CVE-2026-82209 — Ninja Signal Threat Intelligence | Ninja Signal