[AutoPR- Security] Patch curl for CVE-2026-11856 [MEDIUM]

[azurelinux-security]

Auto Patch curl for CVE-2026-11856.

Autosec pipeline run -> https://dev.azure.com/mariner-org/mariner/_build/results?buildId=1163781&view=results

CVE-2026-11856 : Single Patch Backporter Pipeline Run -> https://dev.azure.com/mariner-org/mariner/_build/results?buildId=1163784&view=results

Merge Checklist

All boxes should be checked before merging the PR (just tick any boxes which don't apply to this PR)

• The toolchain has been rebuilt successfully (or no changes were made to it)
• The toolchain/worker package manifests are up-to-date
• Any updated packages successfully build (or no packages were changed)
• Packages depending on static components modified in this PR (Golang, *-static subpackages, etc.) have had their Release tag incremented.
• Package tests (%check section) have been verified with RUN_CHECK=y for existing SPEC files, or added to new SPEC files
• All package sources are available
• cgmanifest files are up-to-date and sorted (./cgmanifest.json, ./toolkit/scripts/toolchain/cgmanifest.json, .github/workflows/cgmanifest.json)
• LICENSE-MAP files are up-to-date (./LICENSES-AND-NOTICES/SPECS/data/licenses.json, ./LICENSES-AND-NOTICES/SPECS/LICENSES-MAP.md, ./LICENSES-AND-NOTICES/SPECS/LICENSE-EXCEPTIONS.PHOTON)
• All source files have up-to-date hashes in the *.signatures.json files
• sudo make go-tidy-all and sudo make go-test-coverage pass
• Documentation has been updated to match any changes to the build system
• Ready to merge

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Summary

What does the PR accomplish, why was it needed?

• Auto Patch curl for CVE-2026-11856 (MEDIUM).

Change Log

• CVE-2026-11856

Does this affect the toolchain?

YES/NO

Associated issues

• N/A

Links to CVEs

• https://nvd.nist.gov/vuln/detail/CVE-2026-11856

Test Methodology

• Pipeline build id: Buddy Build URL

[azure-pipelines]

Azure Pipelines:
There may be pipelines that require an authorized user to comment /azp run to run.

[AkarshHCL]

1.Ai Backported patch did not fixed the vulnerability had to make changes to the patch.
2.The upstream fix was for the source code which is cred based architecture which azurelinux source code does not have.
3. Did a POC to test if vulnerability is fixed or not, POC link-https://hackerone.com/reports/3793260
4. POC output before fix-

POC output after fix-

5.Buddy Build link-https://dev.azure.com/mariner-org/mariner/_build/results?buildId=1164535&view=results
6. Patch is getting applied cleanly-

[mfrw]

The revised backport builds and passes the normal origin/credential regression test, but its serialized identity keys are not equivalent to upstream and can fail to detect valid credential or destination changes.

Request @kgodara912 to please take a look once

[mfrw]

The way our backport stores credentials, using aprintf does not uniquely identify the (username, password) pair. For example, these valid libcurl inputs serialize identically:

username = "a:b", password = "c"   -> "a:b:c"
username = "a",   password = "b:c" -> "a:b:c"

I think the credential identity is ambigious

also,
origin identity omits upstream destination properties, aprintf usage notably omits conn->scope_id (and any Unix-socket identity), so two destinations that upstream considers different can compare equal.