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Neal Patel f0c69db15a [release-branch.go1.25] crypto/x509: improve domain name verification
Don't use domainToReverseLabels to check if domain names are valid,
since it is not particularly performant, and can contribute to DoS
vectors. Instead just iterate over the name and enforce the properties
we care about.

This also enforces that DNS names, both in SANs and name constraints,
are valid. We previously allowed invalid SANs, because some
intermediates had these weird names (see #23995), but there are
currently no trusted intermediates that have this property, and since we
target the web PKI, supporting this particular case is not a high
priority.

Thank you to Jakub Ciolek for reporting this issue.

Fixes CVE-2025-58187
For #75681
Fixes #75715

Change-Id: I6ebce847dcbe5fc63ef2f9a74f53f11c4c56d3d1
Reviewed-on: https://go-internal-review.googlesource.com/c/go/+/2820
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Roland Shoemaker <bracewell@google.com>
Reviewed-on: https://go-internal-review.googlesource.com/c/go/+/2981
Commit-Queue: Roland Shoemaker <bracewell@google.com>
Reviewed-by: Nicholas Husin <husin@google.com>
Reviewed-on: https://go-review.googlesource.com/c/go/+/709848
Auto-Submit: Michael Pratt <mpratt@google.com>
TryBot-Bypass: Michael Pratt <mpratt@google.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
2025-10-07 11:02:15 -07:00
.github .github: update language change proposal template 2024-08-08 19:02:29 +00:00
api testing: add Output method to TB 2025-06-02 09:09:57 -07:00
doc [release-branch.go1.25] spec: revert "update spec date to match release date" 2025-10-06 14:12:00 -07:00
lib [release-branch.go1.25] lib/fips140: re-seal v1.0.0 2025-09-26 10:44:50 -07:00
misc misc/linkcheck: remove unused tool 2025-03-20 04:38:55 -07:00
src [release-branch.go1.25] crypto/x509: improve domain name verification 2025-10-07 11:02:15 -07:00
test [release-branch.go1.25] cmd/compile: don't rely on loop info when there are irreducible loops 2025-10-01 11:40:47 -07:00
.gitattributes all: treat all files as binary, but check in .bat with CRLF 2020-06-08 15:31:43 +00:00
.gitignore runtime,internal: move runtime/internal/sys to internal/runtime/sys 2024-07-23 19:05:35 +00:00
codereview.cfg [release-branch.go1.25] update codereview.cfg for release-branch.go1.25 2025-06-06 12:45:11 -07:00
CONTRIBUTING.md doc: normalize proposal-process links 2023-03-29 22:00:27 +00:00
go.env cmd/go: additional doc-inspired tests and bug fixes 2023-06-06 19:18:46 +00:00
LICENSE LICENSE: update per Google Legal 2024-08-09 14:54:31 +00:00
PATENTS LICENSE: separate, change PATENTS text 2010-12-06 16:31:59 -05:00
README.md README: fix CC BY license name 2024-07-22 17:45:27 +00:00
SECURITY.md SECURITY.md: update the Reporting a Vulnerability link 2023-09-22 21:17:24 +00:00
VERSION [release-branch.go1.25] go1.25.1 2025-09-03 10:46:11 -07:00

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