fix(security/unknown/): update go toolchain directive to v1.26.6 [security]

[renovate-sh-app]

This PR contains the following updates:

Package	Type	Update	Change
go (source)	toolchain	patch	1.26.5 → 1.26.6

---

Warning

Some dependencies could not be looked up. Check the Dependency Dashboard for more information.

---

Invoking failure to reject ASCII-only Punycode-encoded labels in golang.org/x/net/idna

CVE-2026-39821 / GO-2026-5026

More information

Details

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode("xn--example-.com") incorrectly returns the name "example.com" rather than an error.

This behavior can lead to privilege escalation in programs using the idna package. For example, a program which performs privilege checks on the ASCII hostname may reject "example.com" but permit "xn--example-.com". If that program subsequently converts the ASCII hostname to Unicode, it will inadvertently permits access to the Unicode name "example.com".

Severity

Unknown

References

• https://go.dev/cl/767220
• https://go.dev/issue/78760
• https://groups.google.com/g/golang-announce/c/iI-mYSI0lu8
• https://groups.google.com/g/golang-announce/c/94pEornpRlI

This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).

---

Parsing an invalid SVCB or HTTPS RR can panic in golang.org/x/net/dns/dnsmessage

CVE-2026-46600 / GO-2026-5942

More information

Details

Parsing an invalid SVCB or HTTPS RR can panic when the size of a parameter value overflows the message buffer.

Severity

Unknown

References

• https://go.dev/cl/786345
• https://go.dev/issue/79795
• https://groups.google.com/g/golang-announce/c/94pEornpRlI

This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).

---

Enforce maximum recursion depth in encoding/asn1

CVE-2026-33818 / GO-2026-5972

More information

Details

Enforce a recursion limit in Unmarshal to prevent stack exhaustion when parsing deeply-nested, recursive structures.

Severity

Unknown

References

• https://go.dev/issue/80405
• https://groups.google.com/g/golang-announce/c/94pEornpRlI
• https://go.dev/cl/814980

This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).

---

Add recursion depth guard during decode in encoding/xml

CVE-2026-56859 / GO-2026-6088

More information

Details

Previously, DecodeElement would reset the depth counter causing it to never fire; this could lead to stack exhaustion.

Severity

Unknown

References

• https://go.dev/issue/80481
• https://go.dev/cl/803320
• https://groups.google.com/g/golang-announce/c/94pEornpRlI

This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).

---

Apply ReadHeaderTimeout when doing unencrypted HTTP/2 check in net/http

CVE-2026-56853 / GO-2026-6089

More information

Details

When a server is configured to support unencrypted HTTP/2, it reads a few bytes from each new connection to see if they contain the HTTP/2 client preface. ReadHeaderTimeout is unexpectedly not being applied when doing this.

Severity

Unknown

References

• https://go.dev/issue/80205
• https://go.dev/cl/795540
• https://groups.google.com/g/golang-announce/c/94pEornpRlI

This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).

---

Limit handshake messages we are willing to accept post-handshake in crypto/tls

CVE-2026-56862 / GO-2026-6090

More information

Details

Handshake messages, such as KeyUpdate, are always considered as state-advancing, regardless of whether a handshake has been completed or not. As a result, a malicious client can keep sending KeyUpdate messages to force the server to keep performing key derivation operations indefinitely.

Severity

Unknown

References

• https://go.dev/issue/80528
• https://go.dev/cl/804261
• https://groups.google.com/g/golang-announce/c/94pEornpRlI

This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).

---

Fix Javascript regexp context tracking in html/template

CVE-2026-56858 / GO-2026-6091

More information

Details

Previously, pathological inputs could close an unescaped '/' early, allowing for attack-controlled data to inject arbitrary content, potentially leading to XSS.

Severity

Unknown

References

• https://go.dev/issue/80435
• https://go.dev/cl/807100
• https://groups.google.com/g/golang-announce/c/94pEornpRlI

This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).

---

Avoid quadratic complexity in resolvePath in net/url

CVE-2026-56860 / GO-2026-6218

More information

Details

Previously, resolving relative paths containing parent directory ('..') segments performed string conversions and buffer rewrites on each step, resulting in quadratic time complexity and high memory allocation overhead.

Now, path resolution operates on a byte buffer using index-based backtracking for '..' segments, eliminating the quadratic time complexity and significantly reducing memory allocations.

Severity

Unknown

References

• https://go.dev/cl/803681
• https://go.dev/issue/80494
• https://groups.google.com/g/golang-announce/c/94pEornpRlI

This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).

---

Configuration

📅 Schedule: (UTC)

• Branch creation
  • At any time (no schedule defined)
• Automerge
  • At any time (no schedule defined)

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

• If you want to rebase/retry this PR, check this box

---

Need help?

You can ask for more help in the following Slack channel: #proj-renovate-self-hosted. In that channel you can also find ADR and FAQ docs in the Resources section.