diff --git a/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala b/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala
index 4da407fd31c..ac9b5a9d62e 100644
--- a/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala
+++ b/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala
@@ -423,6 +423,8 @@ class DatasetResource extends LazyLogging {
         throw new ForbiddenException(ERR_USER_HAS_NO_ACCESS_TO_DATASET_MESSAGE)
       }
 
+      ResourceNaming.validateVersionDescription(versionName)
+
       val dataset = getDatasetByID(ctx, did)
       val datasetName = dataset.getName
       val repositoryName = dataset.getRepositoryName
diff --git a/file-service/src/main/scala/org/apache/texera/service/resource/ModelResource.scala b/file-service/src/main/scala/org/apache/texera/service/resource/ModelResource.scala
index 80a69cbda2a..a9a6fa6f1d0 100644
--- a/file-service/src/main/scala/org/apache/texera/service/resource/ModelResource.scala
+++ b/file-service/src/main/scala/org/apache/texera/service/resource/ModelResource.scala
@@ -741,6 +741,8 @@ class ModelResource extends LazyLogging {
         throw new ForbiddenException(ERR_USER_HAS_NO_ACCESS_TO_MODEL_MESSAGE)
       }
 
+      ResourceNaming.validateVersionDescription(versionName)
+
       val model = getModelByID(ctx, mid)
       val modelName = model.getName
       val repositoryName = model.getRepositoryName
diff --git a/file-service/src/main/scala/org/apache/texera/service/resource/ResourceNaming.scala b/file-service/src/main/scala/org/apache/texera/service/resource/ResourceNaming.scala
index 7a71362256c..b378e74d12f 100644
--- a/file-service/src/main/scala/org/apache/texera/service/resource/ResourceNaming.scala
+++ b/file-service/src/main/scala/org/apache/texera/service/resource/ResourceNaming.scala
@@ -54,6 +54,22 @@ object ResourceNaming {
     }
   }
 
+  /**
+    * Rejects a version description containing "/". The version name is a segment of the logical
+    * path /<prefix>/ownerEmail/resourceName/versionName/file, which FileResolver splits on "/", so
+    * none of such a version's files could be opened. A null or empty description is allowed: the
+    * version is then named by its number alone.
+    *
+    * @throws jakarta.ws.rs.BadRequestException if the description contains a "/".
+    */
+  def validateVersionDescription(description: String): Unit =
+    if (description != null && description.contains("/")) {
+      throw new BadRequestException(
+        "Invalid version description: '/' is not allowed because the version name is part of " +
+          "the paths of its files."
+      )
+    }
+
   /**
     * Validates a file path supplied for a resource's contents.
     *
diff --git a/file-service/src/test/scala/org/apache/texera/service/resource/DatasetResourceSpec.scala b/file-service/src/test/scala/org/apache/texera/service/resource/DatasetResourceSpec.scala
index db4c2437ebd..9361e46a70f 100644
--- a/file-service/src/test/scala/org/apache/texera/service/resource/DatasetResourceSpec.scala
+++ b/file-service/src/test/scala/org/apache/texera/service/resource/DatasetResourceSpec.scala
@@ -3975,4 +3975,21 @@ class DatasetResourceSpec
     assertStatus(ex, 400)
     datasetResource.getDatasetVersionList(dataset.getDid, sessionUser) should have size 1
   }
+
+  it should "reject a description containing a slash without committing" in {
+    val dataset = seedDatasetWithStagedFile("version-slash")
+
+    val ex = intercept[WebApplicationException] {
+      createVersion(dataset, "2024/01 snapshot")
+    }
+    assertStatus(ex, 400)
+
+    // Nothing was committed: the file is still staged and no version row exists, so the retry
+    // with a usable description succeeds as the first version.
+    LakeFSStorageClient
+      .retrieveUncommittedObjects(dataset.getRepositoryName)
+      .map(_.getPath) shouldBe List("staged.txt")
+    val retried = createVersion(dataset, "2024-01 snapshot")
+    retried.datasetVersion.getName shouldBe "v1 - 2024-01 snapshot"
+  }
 }
diff --git a/file-service/src/test/scala/org/apache/texera/service/resource/ModelUploadResourceSpec.scala b/file-service/src/test/scala/org/apache/texera/service/resource/ModelUploadResourceSpec.scala
index f4f300b7dcf..70bfc0d0d3a 100644
--- a/file-service/src/test/scala/org/apache/texera/service/resource/ModelUploadResourceSpec.scala
+++ b/file-service/src/test/scala/org/apache/texera/service/resource/ModelUploadResourceSpec.scala
@@ -326,6 +326,21 @@ class ModelUploadResourceSpec
       .map(_.getName) should contain("weights.pt")
   }
 
+  it should "reject a description containing a slash without committing to LakeFS" in {
+    val model = newModel()
+    val mid = model.model.getMid
+
+    uploadOneShot(mid, "weights.pt", Array.fill[Byte](32)(0x1)).getStatus shouldEqual 200
+
+    intercept[BadRequestException] {
+      modelResource.createModelVersion("2024/01 snapshot", mid, sessionUser)
+    }
+
+    // The staged change survived, so a retry with a usable description works.
+    val recovered = modelResource.createModelVersion("2024-01 snapshot", mid, sessionUser)
+    recovered.modelVersion.getName should endWith("2024-01 snapshot")
+  }
+
   "retrieveModelVersionRootFileNodes" should "404 for a version belonging to another model" in {
     val modelA = newModel()
     val modelB = newModel()
diff --git a/file-service/src/test/scala/org/apache/texera/service/resource/ResourceNamingSpec.scala b/file-service/src/test/scala/org/apache/texera/service/resource/ResourceNamingSpec.scala
index 71e6812eb6b..fd23cdd2438 100644
--- a/file-service/src/test/scala/org/apache/texera/service/resource/ResourceNamingSpec.scala
+++ b/file-service/src/test/scala/org/apache/texera/service/resource/ResourceNamingSpec.scala
@@ -23,9 +23,9 @@ import jakarta.ws.rs.BadRequestException
 import org.scalatest.flatspec.AnyFlatSpec
 import org.scalatest.matchers.should.Matchers
 
-// Focused unit tests for ResourceNaming.validateAndNormalizeFilePathOrThrow, which guards
-// every upload/lookup path. These call the pure helper directly and avoid the heavy
-// DatasetResourceSpec integration harness (DB + LakeFS).
+// Focused unit tests for ResourceNaming's pure validators: validateAndNormalizeFilePathOrThrow,
+// which guards every upload/lookup path, and validateVersionDescription. These call the helpers
+// directly and avoid the heavy DatasetResourceSpec integration harness (DB + LakeFS).
 class ResourceNamingSpec extends AnyFlatSpec with Matchers {
 
   "validateAndNormalizeFilePathOrThrow" should "reject a null path" in {
@@ -76,4 +76,25 @@ class ResourceNamingSpec extends AnyFlatSpec with Matchers {
       "a/./b/../c.csv"
     ) shouldBe "a/c.csv"
   }
+
+  "validateVersionDescription" should "reject a description containing a slash anywhere" in {
+    Seq("/", "2024/01 snapshot", "/leading", "trailing/", "a//b").foreach { description =>
+      val ex = intercept[BadRequestException] {
+        ResourceNaming.validateVersionDescription(description)
+      }
+      ex.getMessage should include("'/'")
+    }
+  }
+
+  it should "accept a null or empty description, which names the version by its number alone" in {
+    ResourceNaming.validateVersionDescription(null)
+    ResourceNaming.validateVersionDescription("")
+  }
+
+  it should "accept any description without a slash" in {
+    Seq("second upload", "2024-01 snapshot", "a\\b", "naïve 数据 \uD83D\uDE00", " ")
+      .foreach {
+        ResourceNaming.validateVersionDescription
+      }
+  }
 }
diff --git a/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.html b/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.html
index 384d706f600..1829cc611e9 100644
--- a/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.html
+++ b/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.html
@@ -158,14 +158,24 @@
           [(ngModel)]="versionName"
           placeholder="Describe the new version (Optional)"
           [disabled]="isCreatingVersion"
+          [attr.aria-invalid]="versionNameHasSlash ? 'true' : null"
+          [attr.aria-describedby]="versionNameHasSlash ? 'version-name-error' : null"
           (keydown.enter)="onClickCreateVersion()"
           class="version-input" />
       </div>
+      <div
+        *ngIf="versionNameHasSlash"
+        id="version-name-error"
+        role="alert"
+        class="version-name-error">
+        A version description cannot contain '/'.
+      </div>
       <div>
         <button
           nz-button
           nzType="primary"
           [nzLoading]="isCreatingVersion"
+          [disabled]="versionNameHasSlash"
           (click)="onClickCreateVersion()"
           class="create-version-button">
           Submit
diff --git a/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.scss b/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.scss
index 788b226a408..d4944a608f0 100644
--- a/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.scss
+++ b/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.scss
@@ -90,6 +90,11 @@
   padding: 6px;
 }
 
+.version-name-error {
+  margin-top: 6px;
+  color: #ff4d4f;
+}
+
 .create-version-button {
   display: flex; /* Use flexbox for centering */
   align-items: center; /* Center vertically */
diff --git a/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.spec.ts b/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.spec.ts
index 754bf14eebd..499a84034ec 100644
--- a/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.spec.ts
+++ b/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.spec.ts
@@ -1175,6 +1175,46 @@ describe("VersionUploaderComponent", () => {
         expect(createVersionSpy).toHaveBeenCalledWith("second cut");
       });
 
+      it("explains why a name with a slash is refused and keeps Submit from sending it", () => {
+        const el = withPendingChanges();
+        const submit = q<HTMLButtonElement>(el, ".create-version-button");
+
+        const input = typeName(el, "/");
+
+        expect(text(q<HTMLElement>(el, ".version-name-error"))).toBe("A version description cannot contain '/'.");
+        expect(submit.disabled).toBe(true);
+        // Enter submits straight from the field, so it must not get around the disabled button.
+        input.dispatchEvent(new KeyboardEvent("keydown", { key: "Enter", bubbles: true }));
+        expect(createVersionSpy).not.toHaveBeenCalled();
+
+        // Fixing the name takes the error away and re-enables Submit.
+        typeName(el, "2024-01 snapshot");
+
+        expect(el.querySelector(".version-name-error")).toBeNull();
+        expect(submit.disabled).toBe(false);
+      });
+
+      it("announces the slash error to assistive tech and ties it to the name field", () => {
+        const el = withPendingChanges();
+        const input = q<HTMLInputElement>(el, ".version-input");
+        expect(input.getAttribute("aria-invalid")).toBeNull();
+        expect(input.getAttribute("aria-describedby")).toBeNull();
+
+        typeName(el, "/");
+
+        const error = q<HTMLElement>(el, ".version-name-error");
+        expect(error.getAttribute("role")).toBe("alert");
+        expect(input.getAttribute("aria-invalid")).toBe("true");
+        // The input must point at the message that is actually on the page.
+        expect(error.id).not.toBe("");
+        expect(input.getAttribute("aria-describedby")).toBe(error.id);
+
+        typeName(el, "2024-01 snapshot");
+
+        expect(input.getAttribute("aria-invalid")).toBeNull();
+        expect(input.getAttribute("aria-describedby")).toBeNull();
+      });
+
       it("submits the version straight from the name field with Enter", () => {
         const el = withPendingChanges();
 
diff --git a/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.ts b/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.ts
index cfdaca02e6f..860d3226a30 100644
--- a/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.ts
+++ b/frontend/src/app/dashboard/component/user/version-uploader/version-uploader.component.ts
@@ -452,8 +452,16 @@ export class VersionUploaderComponent implements OnInit {
     this.userHasPendingChanges = this.pendingChangesCount > 0;
   }
 
+  /**
+   * The name becomes a segment of the version's file paths, which are split on "/", so a version
+   * named with one could never have its files opened.
+   */
+  get versionNameHasSlash(): boolean {
+    return this.versionName.includes("/");
+  }
+
   onClickCreateVersion(): void {
-    if (!this.resourceId || this.isCreatingVersion) {
+    if (!this.resourceId || this.isCreatingVersion || this.versionNameHasSlash) {
       return;
     }
     this.isCreatingVersion = true;