diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 55f1954..1fd1f45 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -13,6 +13,9 @@ jobs:
     runs-on: ubuntu-latest
     permissions:
       contents: write
+      id-token: write
+      attestations: write
+      artifact-metadata: write
     steps:
       - name: Checkout
         uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
@@ -27,9 +30,18 @@ jobs:
         run: |
           chmod +x ./gradlew
           ./gradlew check releaseBundle
+      - name: Generate release provenance attestation
+        uses: actions/attest-build-provenance@a2bbfa25375fe432b6a289bc6b6cd05ecd0c4c32 # v4.1.0
+        with:
+          subject-path: build/release/network-chat-*-windows.zip
+      - name: Generate SBOM attestation
+        uses: actions/attest@59d89421af93a897026c735860bf21b6eb4f7b26 # v4.1.0
+        with:
+          subject-path: build/release/network-chat-*-windows.zip
+          sbom-path: build/release/network-chat-*-sbom.cdx.json
       - name: Upload release assets
         if: github.event_name == 'release'
         env:
           GH_TOKEN: ${{ github.token }}
         run: |
-          gh release upload "${GITHUB_REF_NAME}" build/release/*.zip build/release/checksums.txt build/release/provenance.json --clobber
+          gh release upload "${GITHUB_REF_NAME}" build/release/*.zip build/release/checksums.txt build/release/provenance.json build/release/*-sbom.cdx.json --clobber
diff --git a/README.en.md b/README.en.md
index c1daa12..2463572 100644
--- a/README.en.md
+++ b/README.en.md
@@ -19,7 +19,7 @@ Network Chat is a Java 21 chat application over TCP sockets with:
 - optional file-backed message history with room replay after server restart.
 - optional TLS mode, token-based accounts with `USER`/`ADMIN` roles, and the admin `/health`
   command.
-- a Windows release zip with launch scripts, checksums, and provenance metadata.
+- a Windows release zip with launch scripts, checksums, CycloneDX SBOM, and provenance metadata.
 - reproducible Gradle build, tests, CI, and quality gates.
 
 ![Swing GUI client](docs/images/gui-client.svg)
@@ -84,7 +84,14 @@ To build a no-Gradle release package for end users:
 ./gradlew releaseBundle
 ```
 
-Artifacts are written to `build/release`: the Windows zip, `checksums.txt`, and `provenance.json`.
+Artifacts are written to `build/release`: the Windows zip, `checksums.txt`, CycloneDX SBOM, and `provenance.json`.
+
+Release verification:
+
+```bash
+sha256sum -c checksums.txt
+gh attestation verify network-chat-*-windows.zip --repo krotname/JavaNetworkChat
+```
 
 ## Architecture and protocol
 
@@ -177,6 +184,7 @@ This repository is organized for maintainability:
 - Automated quality gates via Checkstyle, Spotless, SpotBugs and JaCoCo.
 - Security checks via CodeQL and OpenSSF Scorecard.
 - Dependency and workflow automation via Dependabot.
+- Release artifacts: zip, `checksums.txt`, CycloneDX SBOM, provenance metadata, and GitHub attestations.
 - Explicit contributor and security docs.
 
 ## Troubleshooting
diff --git a/README.md b/README.md
index c6c3bb8..dbb4183 100644
--- a/README.md
+++ b/README.md
@@ -24,7 +24,7 @@ Network Chat — это Java 21 приложение для сетевого ч
 - опциональная файловая история сообщений с replay последних сообщений комнаты после рестарта;
 - опциональный TLS-режим, token-based accounts с ролями `USER`/`ADMIN` и admin-команда
   `/health`;
-- Windows release zip с launch scripts, checksums и provenance metadata;
+- Windows release zip с launch scripts, checksums, CycloneDX SBOM и provenance metadata;
 - воспроизводимая Gradle-сборка, тесты, CI и проверки качества.
 
 ![Swing GUI client](docs/images/gui-client.svg)
@@ -82,7 +82,14 @@ $env:NETWORK_CHAT_TRUSTSTORE_PASSWORD="changeit"
 ./gradlew releaseBundle
 ```
 
-Артефакты появятся в `build/release`: Windows zip, `checksums.txt` и `provenance.json`.
+Артефакты появятся в `build/release`: Windows zip, `checksums.txt`, CycloneDX SBOM и `provenance.json`.
+
+Проверка релиза:
+
+```bash
+sha256sum -c checksums.txt
+gh attestation verify network-chat-*-windows.zip --repo krotname/JavaNetworkChat
+```
 
 ## Архитектура и протокол
 
@@ -160,6 +167,7 @@ Actions Summary для Linux job.
 - Авто-проверки: Checkstyle, Spotless, SpotBugs, JaCoCo.
 - Security проверки: CodeQL и OpenSSF Scorecard.
 - Dependabot с группировкой обновлений зависимостей и Actions.
+- Релизные артефакты: zip, `checksums.txt`, CycloneDX SBOM, provenance metadata и GitHub attestations.
 - Явно оформленные файлы `CONTRIBUTING.md` и `SECURITY.md`.
 
 ## Roadmap
diff --git a/SECURITY.md b/SECURITY.md
index dfdc014..810a702 100644
--- a/SECURITY.md
+++ b/SECURITY.md
@@ -34,7 +34,7 @@ Protected assets:
 - chat message contents in transit when TLS is enabled,
 - account tokens stored only as salted SHA-256 hashes in the optional accounts file,
 - server availability under configured client limits,
-- release artifacts and their checksums/provenance metadata.
+- release artifacts, CycloneDX SBOM, checksums, provenance metadata, and GitHub attestations.
 
 Trust boundaries:
 
@@ -59,4 +59,4 @@ Operational recommendations:
 - Enable TLS outside localhost/trusted lab networks.
 - Keep `accounts.csv` readable only by the server operator.
 - Rotate tokens by replacing account-file rows and restarting the server.
-- Publish release zip files together with `checksums.txt` and `provenance.json`.
+- Publish release zip files together with `checksums.txt`, CycloneDX SBOM, `provenance.json`, and GitHub attestations.
diff --git a/build.gradle.kts b/build.gradle.kts
index 1321228..e8d76e3 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -1,5 +1,7 @@
 import java.security.MessageDigest
 import java.time.Instant
+import java.util.UUID
+import groovy.json.JsonOutput
 
 plugins {
     java
@@ -267,6 +269,7 @@ val packageWindowsZip = tasks.register<Zip>("packageWindowsZip") {
 }
 
 val provenanceFile = layout.buildDirectory.file("release/provenance.json")
+val sbomFile = layout.buildDirectory.file("release/$releasePackageName-sbom.cdx.json")
 
 tasks.register("releaseProvenance") {
     group = "distribution"
@@ -306,15 +309,16 @@ tasks.register("releaseProvenance") {
 tasks.register("releaseChecksums") {
     group = "distribution"
     description = "Write SHA-256 checksums for release artifacts"
-    dependsOn(packageWindowsZip, tasks.named("releaseProvenance"))
+    dependsOn(packageWindowsZip, tasks.named("releaseProvenance"), "releaseSbom")
     val checksumsFile = layout.buildDirectory.file("release/checksums.txt")
-    inputs.files(packageWindowsZip.flatMap { it.archiveFile }, provenanceFile)
+    inputs.files(packageWindowsZip.flatMap { it.archiveFile }, provenanceFile, sbomFile)
     outputs.file(checksumsFile)
     doLast {
         val artifacts =
             listOf(
                 packageWindowsZip.get().archiveFile.get().asFile,
                 provenanceFile.get().asFile,
+                sbomFile.get().asFile,
             )
         checksumsFile.get().asFile.writeText(
             artifacts.joinToString(System.lineSeparator()) {
@@ -324,10 +328,52 @@ tasks.register("releaseChecksums") {
     }
 }
 
+tasks.register("releaseSbom") {
+    group = "distribution"
+    description = "Write a CycloneDX SBOM for the release runtime classpath"
+    outputs.file(sbomFile)
+    doLast {
+        val components =
+            configurations.runtimeClasspath.get().resolvedConfiguration.resolvedArtifacts
+                .sortedWith(compareBy({ it.moduleVersion.id.group }, { it.name }, { it.moduleVersion.id.version }))
+                .map {
+                    val id = it.moduleVersion.id
+                    mapOf(
+                        "type" to "library",
+                        "bom-ref" to "pkg:maven/${id.group}/${id.name}@${id.version}",
+                        "group" to id.group,
+                        "name" to id.name,
+                        "version" to id.version,
+                        "purl" to "pkg:maven/${id.group}/${id.name}@${id.version}",
+                    )
+                }
+        val bom =
+            mapOf(
+                "bomFormat" to "CycloneDX",
+                "specVersion" to "1.6",
+                "serialNumber" to "urn:uuid:${UUID.nameUUIDFromBytes("${project.name}:${project.version}".toByteArray())}",
+                "version" to 1,
+                "metadata" to
+                    mapOf(
+                        "timestamp" to Instant.now().toString(),
+                        "component" to
+                            mapOf(
+                                "type" to "application",
+                                "name" to project.name,
+                                "version" to project.version.toString(),
+                                "purl" to "pkg:maven/${project.group}/${project.name}@${project.version}",
+                            ),
+                    ),
+                "components" to components,
+            )
+        sbomFile.get().asFile.writeText(JsonOutput.prettyPrint(JsonOutput.toJson(bom)))
+    }
+}
+
 tasks.register("releaseBundle") {
     group = "distribution"
-    description = "Build release zip, checksums, and provenance metadata"
-    dependsOn(packageWindowsZip, tasks.named("releaseProvenance"), tasks.named("releaseChecksums"))
+    description = "Build release zip, checksums, SBOM, and provenance metadata"
+    dependsOn(packageWindowsZip, tasks.named("releaseProvenance"), tasks.named("releaseSbom"), tasks.named("releaseChecksums"))
 }
 
 fun sha256(file: File): String {