diff --git a/__tests__/util.test.ts b/__tests__/util.test.ts
index 76fe4e1..2649662 100644
--- a/__tests__/util.test.ts
+++ b/__tests__/util.test.ts
@@ -1,5 +1,7 @@
 import * as config from '../src/internal/shared/config'
 import * as util from '../src/internal/shared/util'
+import {maskSigUrl, maskSecretUrls} from '../src/internal/shared/util'
+import {setSecret, debug} from '@actions/core'
 
 export const testRuntimeToken =
   'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwic2NwIjoiQWN0aW9ucy5FeGFtcGxlIEFjdGlvbnMuQW5vdGhlckV4YW1wbGU6dGVzdCBBY3Rpb25zLlJlc3VsdHM6Y2U3ZjU0YzctNjFjNy00YWFlLTg4N2YtMzBkYTQ3NWY1ZjFhOmNhMzk1MDg1LTA0MGEtNTI2Yi0yY2U4LWJkYzg1ZjY5Mjc3NCIsImlhdCI6MTUxNjIzOTAyMn0.XYnI_wHPBlUi1mqYveJnnkJhp4dlFjqxzRmISPsqfw8'
@@ -59,3 +61,159 @@ describe('get-backend-ids-from-token', () => {
     )
   })
 })
+
+jest.mock('@actions/core')
+
+describe('maskSigUrl', () => {
+  beforeEach(() => {
+    jest.clearAllMocks()
+  })
+
+  it('does nothing if no sig parameter is present', () => {
+    const url = 'https://example.com'
+    maskSigUrl(url)
+    expect(setSecret).not.toHaveBeenCalled()
+  })
+
+  it('masks the sig parameter in the middle of the URL and sets it as a secret', () => {
+    const url = 'https://example.com/?param1=value1&sig=12345&param2=value2'
+    maskSigUrl(url)
+    expect(setSecret).toHaveBeenCalledWith('12345')
+    expect(setSecret).toHaveBeenCalledWith(encodeURIComponent('12345'))
+  })
+
+  it('does nothing if the URL is empty', () => {
+    const url = ''
+    maskSigUrl(url)
+    expect(setSecret).not.toHaveBeenCalled()
+  })
+
+  it('handles URLs with fragments', () => {
+    const url = 'https://example.com?sig=12345#fragment'
+    maskSigUrl(url)
+    expect(setSecret).toHaveBeenCalledWith('12345')
+    expect(setSecret).toHaveBeenCalledWith(encodeURIComponent('12345'))
+  })
+})
+
+describe('maskSigUrl handles special characters in signatures', () => {
+  beforeEach(() => {
+    jest.clearAllMocks()
+  })
+
+  it('handles signatures with slashes', () => {
+    const url = 'https://example.com/?sig=abc/123'
+    maskSigUrl(url)
+    expect(setSecret).toHaveBeenCalledWith('abc/123')
+    expect(setSecret).toHaveBeenCalledWith('abc%2F123')
+  })
+
+  it('handles signatures with plus signs', () => {
+    const url = 'https://example.com/?sig=abc+123'
+    maskSigUrl(url)
+    expect(setSecret).toHaveBeenCalledWith('abc 123')
+    expect(setSecret).toHaveBeenCalledWith('abc%20123')
+  })
+
+  it('handles signatures with equals signs', () => {
+    const url = 'https://example.com/?sig=abc=123'
+    maskSigUrl(url)
+    expect(setSecret).toHaveBeenCalledWith('abc=123')
+    expect(setSecret).toHaveBeenCalledWith('abc%3D123')
+  })
+
+  it('handles already percent-encoded signatures', () => {
+    const url = 'https://example.com/?sig=abc%2F123%3D'
+    maskSigUrl(url)
+    expect(setSecret).toHaveBeenCalledWith('abc/123=')
+    expect(setSecret).toHaveBeenCalledWith('abc%2F123%3D')
+  })
+
+  it('handles complex Azure SAS signatures', () => {
+    const url =
+      'https://example.com/container/file.txt?sig=nXyQIUj%2F%2F06Cxt80pBRYiiJlYqtPYg5sz%2FvEh5iHAhw%3D&se=2023-12-31'
+    maskSigUrl(url)
+    expect(setSecret).toHaveBeenCalledWith(
+      'nXyQIUj//06Cxt80pBRYiiJlYqtPYg5sz/vEh5iHAhw='
+    )
+    expect(setSecret).toHaveBeenCalledWith(
+      'nXyQIUj%2F%2F06Cxt80pBRYiiJlYqtPYg5sz%2FvEh5iHAhw%3D'
+    )
+  })
+
+  it('handles signatures with multiple special characters', () => {
+    const url = 'https://example.com/?sig=a/b+c=d&e=f'
+    maskSigUrl(url)
+    expect(setSecret).toHaveBeenCalledWith('a/b c=d')
+    expect(setSecret).toHaveBeenCalledWith('a%2Fb%20c%3Dd')
+  })
+})
+
+describe('maskSecretUrls', () => {
+  beforeEach(() => {
+    jest.clearAllMocks()
+  })
+
+  it('masks sig parameters in signed_upload_url and signed_url', () => {
+    const body = {
+      signed_upload_url: 'https://upload.com?sig=upload123',
+      signed_url: 'https://download.com?sig=download123'
+    }
+    maskSecretUrls(body)
+    expect(setSecret).toHaveBeenCalledWith('upload123')
+    expect(setSecret).toHaveBeenCalledWith(encodeURIComponent('upload123'))
+    expect(setSecret).toHaveBeenCalledWith('download123')
+    expect(setSecret).toHaveBeenCalledWith(encodeURIComponent('download123'))
+  })
+
+  it('handles case where only upload_url is present', () => {
+    const body = {
+      signed_upload_url: 'https://upload.com?sig=upload123'
+    }
+    maskSecretUrls(body)
+    expect(setSecret).toHaveBeenCalledWith('upload123')
+    expect(setSecret).toHaveBeenCalledWith(encodeURIComponent('upload123'))
+  })
+
+  it('handles case where only download_url is present', () => {
+    const body = {
+      signed_url: 'https://download.com?sig=download123'
+    }
+    maskSecretUrls(body)
+    expect(setSecret).toHaveBeenCalledWith('download123')
+    expect(setSecret).toHaveBeenCalledWith(encodeURIComponent('download123'))
+  })
+
+  it('handles case where URLs do not contain sig parameters', () => {
+    const body = {
+      signed_upload_url: 'https://upload.com?token=abc',
+      signed_url: 'https://download.com?token=xyz'
+    }
+    maskSecretUrls(body)
+    expect(setSecret).not.toHaveBeenCalled()
+  })
+
+  it('handles empty string URLs', () => {
+    const body = {
+      signed_upload_url: '',
+      signed_url: ''
+    }
+    maskSecretUrls(body)
+    expect(setSecret).not.toHaveBeenCalled()
+  })
+
+  it('does nothing if body is not an object or is null', () => {
+    maskSecretUrls(null)
+    expect(debug).toHaveBeenCalledWith('body is not an object or is null')
+    expect(setSecret).not.toHaveBeenCalled()
+  })
+
+  it('does nothing if signed_upload_url and signed_url are not strings', () => {
+    const body = {
+      signed_upload_url: 123,
+      signed_url: 456
+    }
+    maskSecretUrls(body)
+    expect(setSecret).not.toHaveBeenCalled()
+  })
+})
diff --git a/src/internal/shared/artifact-twirp-client.ts b/src/internal/shared/artifact-twirp-client.ts
index 00c65bc..5749912 100644
--- a/src/internal/shared/artifact-twirp-client.ts
+++ b/src/internal/shared/artifact-twirp-client.ts
@@ -5,6 +5,7 @@ import {ArtifactServiceClientJSON} from '../../generated'
 import {getResultsServiceUrl, getRuntimeToken} from './config'
 import {getUserAgentString} from './user-agent'
 import {NetworkError, UsageError} from './errors'
+import {maskSecretUrls} from './util'
 
 // The twirp http client must implement this interface
 interface Rpc {
@@ -86,6 +87,7 @@ class ArtifactHttpClient implements Rpc {
         debug(`[Response] - ${response.message.statusCode}`)
         debug(`Headers: ${JSON.stringify(response.message.headers, null, 2)}`)
         const body = JSON.parse(rawBody)
+        maskSecretUrls(body)
         debug(`Body: ${JSON.stringify(body, null, 2)}`)
         if (this.isSuccessStatusCode(statusCode)) {
           return {response, body}
diff --git a/src/internal/shared/util.ts b/src/internal/shared/util.ts
index 07392b3..67120e2 100644
--- a/src/internal/shared/util.ts
+++ b/src/internal/shared/util.ts
@@ -1,6 +1,7 @@
 import * as core from '@actions/core'
 import {getRuntimeToken} from './config'
 import jwt_decode from 'jwt-decode'
+import {debug, setSecret} from '@actions/core'
 
 export interface BackendIds {
   workflowRunBackendId: string
@@ -69,3 +70,76 @@ export function getBackendIdsFromToken(): BackendIds {
 
   throw InvalidJwtError
 }
+
+/**
+ * Masks the `sig` parameter in a URL and sets it as a secret.
+ *
+ * @param url - The URL containing the signature parameter to mask
+ * @remarks
+ * This function attempts to parse the provided URL and identify the 'sig' query parameter.
+ * If found, it registers both the raw and URL-encoded signature values as secrets using
+ * the Actions `setSecret` API, which prevents them from being displayed in logs.
+ *
+ * The function handles errors gracefully if URL parsing fails, logging them as debug messages.
+ *
+ * @example
+ * ```typescript
+ * // Mask a signature in an Azure SAS token URL
+ * maskSigUrl('https://example.blob.core.windows.net/container/file.txt?sig=abc123&se=2023-01-01');
+ * ```
+ */
+export function maskSigUrl(url: string): void {
+  if (!url) return
+  try {
+    const parsedUrl = new URL(url)
+    const signature = parsedUrl.searchParams.get('sig')
+    if (signature) {
+      setSecret(signature)
+      setSecret(encodeURIComponent(signature))
+    }
+  } catch (error) {
+    debug(
+      `Failed to parse URL: ${url} ${
+        error instanceof Error ? error.message : String(error)
+      }`
+    )
+  }
+}
+
+/**
+ * Masks sensitive information in URLs containing signature parameters.
+ * Currently supports masking 'sig' parameters in the 'signed_upload_url'
+ * and 'signed_download_url' properties of the provided object.
+ *
+ * @param body - The object should contain a signature
+ * @remarks
+ * This function extracts URLs from the object properties and calls maskSigUrl
+ * on each one to redact sensitive signature information. The function doesn't
+ * modify the original object; it only marks the signatures as secrets for
+ * logging purposes.
+ *
+ * @example
+ * ```typescript
+ * const responseBody = {
+ *   signed_upload_url: 'https://example.com?sig=abc123',
+ *   signed_download_url: 'https://example.com?sig=def456'
+ * };
+ * maskSecretUrls(responseBody);
+ * ```
+ */
+export function maskSecretUrls(body: Record<string, unknown> | null): void {
+  if (typeof body !== 'object' || body === null) {
+    debug('body is not an object or is null')
+    return
+  }
+
+  if (
+    'signed_upload_url' in body &&
+    typeof body.signed_upload_url === 'string'
+  ) {
+    maskSigUrl(body.signed_upload_url)
+  }
+  if ('signed_url' in body && typeof body.signed_url === 'string') {
+    maskSigUrl(body.signed_url)
+  }
+}