diff --git a/Cargo.lock b/Cargo.lock
index 56cef6c2..5085f79a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -141,6 +141,7 @@ dependencies = [
  "crypto-bigint",
  "crypto-primes",
  "digest",
+ "hex",
  "pkcs8 0.11.0-pre.0",
  "rand",
  "rand_chacha",
@@ -246,6 +247,12 @@ dependencies = [
  "subtle",
 ]
 
+[[package]]
+name = "hex"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7f24254aa9a54b5c858eaee2f5bccdb46aaf0e486a595ed5fd8f86ba55232a70"
+
 [[package]]
 name = "hex-literal"
 version = "0.4.1"
diff --git a/dsa/Cargo.toml b/dsa/Cargo.toml
index f13acd6b..ed651a2d 100644
--- a/dsa/Cargo.toml
+++ b/dsa/Cargo.toml
@@ -16,7 +16,7 @@ rust-version = "1.72"
 
 [dependencies]
 digest = "=0.11.0-pre.7"
-crypto-bigint = { version = "0.6.0-pre.7", features = ["alloc", "zeroize"] }
+crypto-bigint = { version = "0.6.0-pre.12", features = ["alloc", "zeroize"] }
 crypto-primes = "0.6.0-pre.0"
 pkcs8 = { version = "=0.11.0-pre.0", default-features = false, features = ["alloc"] }
 rfc6979 = { version = "=0.5.0-pre.2", path = "../rfc6979" }
@@ -29,6 +29,7 @@ signature = { version = "=2.3.0-pre.2", default-features = false, features = [
 zeroize = { version = "1", default-features = false }
 
 [dev-dependencies]
+hex = "0.4.3"
 pkcs8 = { version = "=0.11.0-pre.0", default-features = false, features = ["pem"] }
 rand = "0.8"
 rand_chacha = "0.3"
diff --git a/dsa/tests/deterministic.rs b/dsa/tests/deterministic.rs
index 3d21e2df..3ed3f265 100644
--- a/dsa/tests/deterministic.rs
+++ b/dsa/tests/deterministic.rs
@@ -8,30 +8,35 @@ use signature::DigestSigner;
 const MESSAGE: &[u8] = b"sample";
 const MESSAGE_2: &[u8] = b"test";
 
+fn decode_hex_number(txt: &str) -> BoxedUint {
+    let val = hex::decode(txt).unwrap();
+    BoxedUint::from_be_slice(&val, val.len() as u32 * 8).unwrap()
+}
+
 fn dsa_1024_signing_key() -> SigningKey {
     let p_str = "86F5CA03DCFEB225063FF830A0C769B9DD9D6153AD91D7CE27F787C43278B447\
                 E6533B86B18BED6E8A48B784A14C252C5BE0DBF60B86D6385BD2F12FB763ED88\
                 73ABFD3F5BA2E0A8C0A59082EAC056935E529DAF7C610467899C77ADEDFC846C\
                 881870B7B19B2B58F9BE0521A17002E3BDD6B86685EE90B3D9A1B02B782B1779";
-    let p = BoxedUint::from_be_hex(p_str, p_str.len() as u32 * 8 / 2).unwrap();
+    let p = decode_hex_number(p_str);
 
     let q_str = "996F967F6C8E388D9E28D01E205FBA957A5698B1";
-    let q = BoxedUint::from_be_hex(q_str, q_str.len() as u32 * 8 / 2).unwrap();
+    let q = decode_hex_number(q_str);
 
     let g_str = "07B0F92546150B62514BB771E2A0C0CE387F03BDA6C56B505209FF25FD3C133D\
             89BBCD97E904E09114D9A7DEFDEADFC9078EA544D2E401AEECC40BB9FBBF78FD\
             87995A10A1C27CB7789B594BA7EFB5C4326A9FE59A070E136DB77175464ADCA4\
             17BE5DCE2F40D10A46A3A3943F26AB7FD9C0398FF8C76EE0A56826A8A88F1DBD";
-    let g = BoxedUint::from_be_hex(g_str, g_str.len() as u32 / 2 * 8).unwrap();
+    let g = decode_hex_number(g_str);
 
     let x_str = "411602CB19A6CCC34494D79D98EF1E7ED5AF25F7";
-    let x = BoxedUint::from_be_hex(x_str, x_str.len() as u32 / 2 * 8).unwrap();
+    let x = decode_hex_number(x_str);
 
     let y_str = "5DF5E01DED31D0297E274E1691C192FE5868FEF9E19A84776454B100CF16F653\
             92195A38B90523E2542EE61871C0440CB87C322FC4B4D2EC5E1E7EC766E1BE8D\
             4CE935437DC11C3C8FD426338933EBFE739CB3465F4D3668C5E473508253B1E6\
             82F65CBDC4FAE93C2EA212390E54905A86E2223170B44EAA7DA5DD9FFCFB7F3B";
-    let y = BoxedUint::from_be_hex(y_str, y_str.len() as u32 / 2 * 8).unwrap();
+    let y = decode_hex_number(y_str);
 
     let (p, q, g, y, x) = (
         NonZero::new(p).unwrap(),
@@ -49,7 +54,7 @@ fn dsa_1024_signing_key() -> SigningKey {
 }
 
 fn dsa_2048_signing_key() -> SigningKey {
-    let p = BoxedUint::from_be_hex(
+    let p = decode_hex_number(
         "9DB6FB5951B66BB6FE1E140F1D2CE5502374161FD6538DF1648218642F0B5C48\
         C8F7A41AADFA187324B87674FA1822B00F1ECF8136943D7C55757264E5A1A44F\
         FE012E9936E00C1D3E9310B01C7D179805D3058B2A9F4BB6F9716BFE6117C6B5\
@@ -58,15 +63,11 @@ fn dsa_2048_signing_key() -> SigningKey {
         F1BF14D4BB4563CA28371621CAD3324B6A2D392145BEBFAC748805236F5CA2FE\
         92B871CD8F9C36D3292B5509CA8CAA77A2ADFC7BFD77DDA6F71125A7456FEA15\
         3E433256A2261C6A06ED3693797E7995FAD5AABBCFBE3EDA2741E375404AE25B",
-        2048,
-    )
-    .unwrap();
-    let q = BoxedUint::from_be_hex(
+    );
+    let q = decode_hex_number(
         "F2C3119374CE76C9356990B465374A17F23F9ED35089BD969F61C6DDE9998C1F",
-        2048,
-    )
-    .unwrap();
-    let g = BoxedUint::from_be_hex(
+    );
+    let g = decode_hex_number(
         "5C7FF6B06F8F143FE8288433493E4769C4D988ACE5BE25A0E24809670716C613\
         D7B0CEE6932F8FAA7C44D2CB24523DA53FBE4F6EC3595892D1AA58C4328A06C4\
         6A15662E7EAA703A1DECF8BBB2D05DBE2EB956C142A338661D10461C0D135472\
@@ -75,16 +76,12 @@ fn dsa_2048_signing_key() -> SigningKey {
         3A10B1C4D203CC76A470A33AFDCBDD92959859ABD8B56E1725252D78EAC66E71\
         BA9AE3F1DD2487199874393CD4D832186800654760E1E34C09E4D155179F9EC0\
         DC4473F996BDCE6EED1CABED8B6F116F7AD9CF505DF0F998E34AB27514B0FFE7",
-        2048,
-    )
-    .unwrap();
+    );
 
-    let x = BoxedUint::from_be_hex(
+    let x = decode_hex_number(
         "69C7548C21D0DFEA6B9A51C9EAD4E27C33D3B3F180316E5BCAB92C933F0E4DBC",
-        2048,
-    )
-    .unwrap();
-    let y = BoxedUint::from_be_hex(
+    );
+    let y = decode_hex_number(
         "667098C654426C78D7F8201EAC6C203EF030D43605032C2F1FA937E5237DBD94\
         9F34A0A2564FE126DC8B715C5141802CE0979C8246463C40E6B6BDAA2513FA61\
         1728716C2E4FD53BC95B89E69949D96512E873B9C8F8DFD499CC312882561ADE\
@@ -93,9 +90,7 @@ fn dsa_2048_signing_key() -> SigningKey {
         687972A2D382599C9BAC4E0ED7998193078913032558134976410B89D2C171D1\
         23AC35FD977219597AA7D15C1A9A428E59194F75C721EBCBCFAE44696A499AFA\
         74E04299F132026601638CB87AB79190D4A0986315DA8EEC6561C938996BEADF",
-        2048,
-    )
-    .unwrap();
+    );
 
     let (p, q, g, y, x) = (
         NonZero::new(p).unwrap(),
@@ -139,8 +134,8 @@ where
 /// Create a signature container from the two components in their textual hexadecimal form
 fn from_str_signature(r: &str, s: &str) -> Signature {
     Signature::from_components(
-        NonZero::new(BoxedUint::from_be_hex(r, r.len() as u32 / 2 * 8).unwrap()).unwrap(),
-        NonZero::new(BoxedUint::from_be_hex(s, s.len() as u32 / 2 * 8).unwrap()).unwrap(),
+        NonZero::new(decode_hex_number(r)).unwrap(),
+        NonZero::new(decode_hex_number(s)).unwrap(),
     )
 }