docs: Breaking change – CRC32 validation added when reading ZIP archive entries (.NET 11 Preview 3)

[Copilot]

Documents the behavioral breaking change in System.IO.Compression where reading a ZIP archive entry now computes and validates the CRC32 checksum, throwing InvalidDataException on mismatch. Previously, corrupted entries were silently read without any integrity check.

Changes

• New article – docs/core/compatibility/core-libraries/11/ziparchive-entry-crc32-validation.md
  • Covers previous/new behavior, reason for change, and recommended action (catch InvalidDataException)
  • Affected API: ZipArchiveEntry.Open
• docs/core/compatibility/11.md – Added entry to the Core .NET libraries table (alphabetical order)
• docs/core/compatibility/toc.yml – Added TOC entry under .NET 11 > Core .NET libraries (alphabetical order)

Behavior snapshot

// .NET 11+: throws InvalidDataException if CRC32 doesn't match ZIP metadata
try
{
    using var archive = ZipFile.OpenRead("example.zip");
    using var stream = archive.GetEntry("file.txt").Open();
    stream.Read(buffer, 0, buffer.Length);
}
catch (InvalidDataException ex)
{
    Console.WriteLine($"Corrupted entry: {ex.Message}");
}

Warning

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If you need me to access, download, or install something from one of these locations, you can either:

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Internal previews

📄 File	🔗 Preview link
docs/core/compatibility/11.md	Breaking changes in .NET 11
docs/core/compatibility/core-libraries/11/ziparchive-entry-crc32-validation.md	CRC32 validation added when reading ZIP archive entries
docs/core/compatibility/toc.yml	docs/core/compatibility/toc

[Copilot]

Pull request overview

Adds a new .NET 11 Core .NET libraries breaking change article documenting that System.IO.Compression now validates CRC32 when reading ZIP entries, and wires the article into the .NET 11 breaking changes index and TOC.

Changes:

• Added a new breaking change article for CRC32 validation on ZIP entry reads (ZipArchiveEntry.Open).
• Linked the new article from docs/core/compatibility/11.md.
• Added the new article to docs/core/compatibility/toc.yml under .NET 11 > Core .NET libraries.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 5 comments.

File	Description
docs/core/compatibility/core-libraries/11/ziparchive-entry-crc32-validation.md	New breaking change article describing CRC32 validation behavior and recommended mitigation.
docs/core/compatibility/11.md	Adds the new breaking change to the .NET 11 Core .NET libraries table.
docs/core/compatibility/toc.yml	Adds a TOC entry for the new breaking change article under .NET 11.

[BillWagner]

This LGTM. Let's

[alinpahontu2912]

LGTM