diff --git a/CHANGELOG.md b/CHANGELOG.md
index 32e14bd1..0b28692a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,7 +14,7 @@ Unreleased
 - Bumped `libc` dependency to `0.2.159`
 - Bumped `serde` dependency to `1.0.147`
 - Bumped `structopt` dependency to `0.3.26`
-- Bumped `toml` dependency to `0.5.9`
+- Bumped `toml` dependency to `0.7.6`
 
 
 0.4.1
diff --git a/Cargo.lock b/Cargo.lock
index 8135d655..0dd12cb2 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -88,6 +88,12 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "equivalent"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5443807d6dff69373d433ab9ef5378ad8df50ca6298caf15de6e52e24aaf54d5"
+
 [[package]]
 name = "fastrand"
 version = "1.7.0"
@@ -128,6 +134,12 @@ dependencies = [
  "anyhow",
 ]
 
+[[package]]
+name = "hashbrown"
+version = "0.15.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e087f84d4f86bf4b218b927129862374b72199ae7d8657835f1e89000eea4fb"
+
 [[package]]
 name = "heck"
 version = "0.3.3"
@@ -137,6 +149,16 @@ dependencies = [
  "unicode-segmentation",
 ]
 
+[[package]]
+name = "indexmap"
+version = "2.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "707907fe3c25f5424cce2cb7e1cbcafee6bdbe735ca90ef77c29e84591e5b9da"
+dependencies = [
+ "equivalent",
+ "hashbrown",
+]
+
 [[package]]
 name = "instant"
 version = "0.1.12"
@@ -425,6 +447,15 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "serde_spanned"
+version = "0.6.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "87607cb1398ed59d48732e575a4c28a7a8ebf2454b964fe3f224f2afc07909e1"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "structopt"
 version = "0.3.26"
@@ -497,11 +528,36 @@ dependencies = [
 
 [[package]]
 name = "toml"
-version = "0.5.9"
+version = "0.7.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8d82e1a7758622a465f8cee077614c73484dac5b836c02ff6a40d5d1010324d7"
+checksum = "c17e963a819c331dcacd7ab957d80bc2b9a9c1e71c804826d2f283dd65306542"
 dependencies = [
  "serde",
+ "serde_spanned",
+ "toml_datetime",
+ "toml_edit",
+]
+
+[[package]]
+name = "toml_datetime"
+version = "0.6.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0dd7358ecb8fc2f8d014bf86f6f638ce72ba252a2c3a2572f2a795f1d23efb41"
+dependencies = [
+ "serde",
+]
+
+[[package]]
+name = "toml_edit"
+version = "0.19.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1b5bb770da30e5cbfde35a2d7b9b8a2c4b8ef89548a7a6aeab5c9a576e3e7421"
+dependencies = [
+ "indexmap",
+ "serde",
+ "serde_spanned",
+ "toml_datetime",
+ "winnow",
 ]
 
 [[package]]
@@ -633,3 +689,12 @@ name = "windows_x86_64_msvc"
 version = "0.48.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ed94fce61571a4006852b7389a063ab983c02eb1bb37b47f8272ce92d06d9538"
+
+[[package]]
+name = "winnow"
+version = "0.5.40"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f593a95398737aeed53e489c785df13f3618e41dbcd6718c6addbf1395aa6876"
+dependencies = [
+ "memchr",
+]
diff --git a/Cargo.toml b/Cargo.toml
index b6f99be1..f149c8f6 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -75,7 +75,7 @@ default-features = false
 version = "1.5.5"
 
 [dependencies.toml]
-version = "0.5.6"
+version = "0.7.6"
 
 [dev-dependencies.nitrokey-test]
 version = "0.5"
diff --git a/ext/otp_cache.rs b/ext/otp_cache.rs
index 12cb4778..8594dc74 100644
--- a/ext/otp_cache.rs
+++ b/ext/otp_cache.rs
@@ -125,8 +125,9 @@ fn save_cache(cache: &Cache, path: &path::Path) -> anyhow::Result<()> {
     fs::create_dir_all(parent).context("Failed to create cache parent directory")?;
   }
   let mut f = fs::File::create(path).context("Failed to create cache file")?;
-  let data = toml::to_vec(cache).context("Failed to serialize cache")?;
-  f.write_all(&data).context("Failed to write cache file")?;
+  let data = toml::to_string(cache).context("Failed to serialize cache")?;
+  f.write_all(data.as_bytes())
+    .context("Failed to write cache file")?;
   Ok(())
 }