Skip to content

fix(cookie): reject Set-Cookie domains that are public suffixes #2091

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
karlseguin merged 1 commit into from
Apr 7, 2026
Merged

fix(cookie): reject Set-Cookie domains that are public suffixes #2091

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
15 changes: 15 additions & 0 deletions src/browser/webapi/storage/Cookie.zig
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -273,6 +273,12 @@ pub fn parseDomain(arena: Allocator, url_: ?[:0]const u8, explicit_domain: ?[]co
// can't set a cookie for a TLD
return error.InvalidDomain;
}

// Can't set a cookie for a public suffix (e.g. co.uk, com.au).
if (public_suffix_list(owned_domain[1..])) {
return error.InvalidDomain;
}

if (encoded_host) |host| {
if (std.mem.endsWith(u8, host, owned_domain[1..]) == false) {
return error.InvalidDomain;
Expand Down Expand Up @@ -1027,6 +1033,15 @@ test "Cookie: parse domain" {
try expectError(error.InvalidDomain, "http://lightpanda.io/", "b;domain=other.lightpanda.io");
try expectError(error.InvalidDomain, "http://lightpanda.io/", "b;domain=other.lightpanda.com");
try expectError(error.InvalidDomain, "http://lightpanda.io/", "b;domain=other.example.com");

// Public suffixes should be rejected (test PSL entries: "gov.uk", "api.gov.uk")
try expectError(error.InvalidDomain, "http://example.gov.uk/", "b;domain=gov.uk");
try expectError(error.InvalidDomain, "http://example.gov.uk/", "b;domain=.gov.uk");
try expectError(error.InvalidDomain, "http://test.api.gov.uk/", "b;domain=api.gov.uk");

// Subdomains of public suffixes should still be accepted
try expectAttribute(.{ .domain = ".example.gov.uk" }, "http://example.gov.uk/", "b;domain=example.gov.uk");
try expectAttribute(.{ .domain = ".example.gov.uk" }, "http://sub.example.gov.uk/", "b;domain=example.gov.uk");
}

test "Cookie: parse limit" {
Expand Down
Loading