diff --git a/server/platform/services/docextractor/archive.go b/server/platform/services/docextractor/archive.go index 1fd89f4472..64309a2b3d 100644 --- a/server/platform/services/docextractor/archive.go +++ b/server/platform/services/docextractor/archive.go @@ -41,6 +41,13 @@ func getExtAlsoTarGz(name string) string { } func (ae *archiveExtractor) Extract(name string, r io.ReadSeeker, maxFileSize int64) (string, error) { + // MM-65701: Skip 7zip files due to OOM vulnerability in bodgit/sevenzip library + match, _ := (archives.SevenZip{}).Match(context.Background(), name, r) + _, _ = r.Seek(0, io.SeekStart) // Reset reader position after Match reads from stream + if match.ByName || match.ByStream { + return "", nil + } + ext := getExtAlsoTarGz(name) // Create a temporary file, using `*` control the random component while preserving the extension. diff --git a/server/platform/services/docextractor/archive_test.go b/server/platform/services/docextractor/archive_test.go new file mode 100644 index 0000000000..729f873a47 --- /dev/null +++ b/server/platform/services/docextractor/archive_test.go @@ -0,0 +1,52 @@ +// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved. +// See LICENSE.txt for license information. + +package docextractor + +import ( + "bytes" + "testing" + + "github.com/stretchr/testify/assert" + "github.com/stretchr/testify/require" +) + +func TestArchiveExtractorSkips7zip(t *testing.T) { + ae := &archiveExtractor{} + + t.Run("7zip file with .7z extension returns empty string", func(t *testing.T) { + // Valid 7zip header (minimal) + sevenZipData := []byte{0x37, 0x7a, 0xbc, 0xaf, 0x27, 0x1c, 0x00, 0x00} + result, err := ae.Extract("test.7z", bytes.NewReader(sevenZipData), 0) + require.NoError(t, err) + assert.Empty(t, result) + }) + + t.Run("7zip content with wrong extension is still blocked", func(t *testing.T) { + // 7zip content disguised with .zip extension - should still be blocked via stream detection + sevenZipData := []byte{0x37, 0x7a, 0xbc, 0xaf, 0x27, 0x1c, 0x00, 0x00} + result, err := ae.Extract("malicious.zip", bytes.NewReader(sevenZipData), 0) + require.NoError(t, err) + assert.Empty(t, result) + }) + + t.Run("7zip at offset with .7z extension is blocked via filename", func(t *testing.T) { + junkPrefix := []byte{0x00, 0x00, 0x00, 0x00} + sevenZipSig := []byte{0x37, 0x7a, 0xbc, 0xaf, 0x27, 0x1c, 0x00, 0x00} + dataWithOffset := append(junkPrefix, sevenZipSig...) + result, err := ae.Extract("test.7z", bytes.NewReader(dataWithOffset), 0) + require.NoError(t, err) + assert.Empty(t, result) + }) + + t.Run("7zip at offset with wrong extension fails safely", func(t *testing.T) { + // Edge case: 7zip content at offset with non-.7z extension. + // Our check won't catch it (ByName=false, ByStream=false), but archives.FileSystem + // also won't identify it as 7zip, so it fails to extract rather than triggering OOM. + junkPrefix := []byte{0x00, 0x00, 0x00, 0x00} + sevenZipSig := []byte{0x37, 0x7a, 0xbc, 0xaf, 0x27, 0x1c, 0x00, 0x00} + dataWithOffset := append(junkPrefix, sevenZipSig...) + _, err := ae.Extract("malicious.zip", bytes.NewReader(dataWithOffset), 0) + assert.Error(t, err) // fails to extract as any valid archive format + }) +}