[AutoPR- Security] Patch nginx for CVE-2026-42055 [HIGH]

[azurelinux-security]

Auto Patch nginx for CVE-2026-42055.

Autosec pipeline run -> https://dev.azure.com/mariner-org/mariner/_build/results?buildId=1150065&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 nginx for CVE-2026-42055 (HIGH).

Change Log

• CVE-2026-42055

Does this affect the toolchain?

YES/NO

Associated issues

• N/A

Links to CVEs

• https://nvd.nist.gov/vuln/detail/CVE-2026-42055

Test Methodology

• Pipeline build id: Buddy Build URL

[azurelinux-security]

🔒 CVE Patch Review: CVE-2026-42055

PR #17871 — [AutoPR- Security] Patch nginx for CVE-2026-42055 [HIGH]
Package: nginx | Branch: fasttrack/3.0

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Spec File Validation

Check	Status	Detail
Release bump	✅	Release bumped 5 → 6
Patch entry	✅	Patch entries added: ['CVE-2026-42055.patch'] (covers ['CVE-2026-42055'])
Patch application	✅	%autosetup/%autopatch found in full spec — patches applied automatically
Changelog	✅	Changelog entry looks good
Signatures	✅	No source tarball changes — signatures N/A
Manifests	✅	Not a toolchain PR — manifests N/A

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Build Verification

• Build status: ✅ PASSED
• Artifact downloaded: ✅
• CVE applied during build: ✅
• Warnings (1):
  • L331: time="2026-06-30T11:39:21Z" level=debug msg="configure: warning: the \"--with-ipv6\" option is deprecated"

🤖 AI Build Log Analysis

• Risk: low
• Summary: The nginx RPM build completed successfully and produced the expected binary, filesystem, and debuginfo RPMs. The requested CVE-2026-42055 patch appears to have been applied during %prep without any reported failures, rejected hunks, fuzz, or offset messages, and the package then configured, compiled, installed, and packaged cleanly.
• AI-detected warnings:
  • RPM emitted a warning about an absolute symlink: /var/log/nginx/log -> /var/opt/nginx/log.
  • RPM emitted a warning that it could not canonicalize the hostname inside the build environment; this appears environmental and did not affect the build.

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🧪 Test Log Analysis

• Test status: ❌ FAILED
• Test warnings (1):
  • L326: time="2026-06-30T11:39:43Z" level=debug msg="configure: warning: the \"--with-ipv6\" option is deprecated"

🤖 AI Test Log Analysis

• Risk: high
• Summary: The nginx package build completed successfully and the %check phase reported an exit status of 0, but the test suite did not actually run as intended. During %check, the harness attempted to execute the nginx upstream Perl tests via su nginx -s /bin/sh -c 'TEST_NGINX_BINARY=/usr/sbin/nginx prove ./*.t', but failed immediately because the nginx user did not exist in the test environment. As a result, no meaningful test validation of the CVE-2026-42055 patch appears to have occurred despite the nominally successful build.
• AI-detected test issues:
  • The %check test invocation failed to start: su nginx -s /bin/sh -c 'TEST_NGINX_BINARY=/usr/sbin/nginx prove ./*.t' returned su: user nginx does not exist or the user entry does not contain all the required fields.
  • The test harness still reported ====== CHECK DONE nginx. EXIT STATUS 0, indicating the failure to execute tests was not propagated as a test failure.
  • Security-relevant upstream nginx tests were present but effectively skipped/not executed because the required runtime user was missing.

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Patch Analysis

• Match type: significant_differences
• Risk assessment: high
• Summary: The PR patch only backports the gRPC-side changes from the upstream fix and omits the entire set of corresponding protections for src/http/modules/ngx_http_proxy_v2_module.c. While the grpc hunks appear functionally equivalent to upstream, the upstream CVE fix covers both HTTP/2/gRPC and proxy_v2 request construction paths, so the Azure patch is incomplete relative to the authoritative patch.
• Missing hunks:
  • All upstream hunks for src/http/modules/ngx_http_proxy_v2_module.c are missing: method length check against NGX_HTTP_V2_MAX_FIELD before encoding
  • All upstream hunks for src/http/modules/ngx_http_proxy_v2_module.c are missing: URI length check against NGX_HTTP_V2_MAX_FIELD
  • All upstream hunks for src/http/modules/ngx_http_proxy_v2_module.c are missing: :authority/host length check against NGX_HTTP_V2_MAX_FIELD
  • All upstream hunks for src/http/modules/ngx_http_proxy_v2_module.c are missing: generic header key/value length checks before length accumulation
  • All upstream hunks for src/http/modules/ngx_http_proxy_v2_module.c are missing: per-header key/value length checks in the later header loop with detailed logging

Detailed analysis

The grpc portion of the PR is a straightforward backport of the upstream changes: it adds the same five classes of bounds checks in ngx_http_grpc_create_request() for method, URI, authority/host, computed key/value lengths, and explicit header key/value lengths, with the same control flow and error handling. The context/index lines differ, but that is normal for a backport and does not indicate a semantic issue in the grpc file. However, upstream modifies two source files and the PR carries only one of them. The entire ngx_http_proxy_v2_module.c half of the fix is absent. Because upstream explicitly applies the same HTTP/2 field size protections in both grpc and proxy_v2 request creation paths, omitting proxy_v2 means the packaged fix does not fully match the authoritative CVE remediation. There is no indication in the provided materials that ngx_http_proxy_v2_module.c is absent from the Azure tree or otherwise intentionally non-applicable, so the missing hunks are not justified based on the evidence shown. As a result, the patch should be considered an incomplete backport with potentially remaining exposure in the proxy_v2 path. Regression risk from the included grpc changes is low by themselves, since they only reject oversize fields before buffer sizing/encoding, but overall security risk remains high due to the missing module coverage.

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Verdict

❌ CHANGES REQUESTED — Please address the issues flagged above.

[xordux]

LGTM

• Patch's code is same as upstream fix.
• Original patch has fix for two files but our version doesn't have ngx_http_proxy_v2_module.c (so it's skipped)
• Github checks failed due to P-Test failure of libguestfs and nbdkit (existing failures)

[xordux]

Release version in 3.0-dev branch is updated. We need to update release version from 6 to 7

Patch is fine.

[xordux]

as discussed with @Kanishk-Bansal these github check failures can be ignored and the release number will be fixed when fasttrack will be merged with dev branch.

[Kanishk-Bansal]

/azurepipelines run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[jslobodzian]

/azurepipelines run

[azure-pipelines]

Azure Pipelines:
Successfully started running 1 pipeline(s).
2 pipeline(s) were filtered out due to trigger conditions.

[CBL-Mariner-Bot]

Auto cherry-pick results:

• 3.0-dev ✅ -> [AUTO-CHERRYPICK] [AutoPR- Security] Patch nginx for CVE-2026-42055 [HIGH] - branch 3.0-dev #17950

Auto cherry-pick pipeline run -> https://dev.azure.com/mariner-org/mariner/_build/results?buildId=1155859&view=results