diff --git a/Cargo.lock b/Cargo.lock
index ca8ce060..b738b0b2 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -124,12 +124,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "curl-sys"
-version = "0.4.5"
+version = "0.4.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cc 1.0.29 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
- "libz-sys 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libz-sys 1.0.18 (registry+https://github.com/rust-lang/crates.io-index)",
  "openssl-sys 0.9.53 (registry+https://github.com/rust-lang/crates.io-index)",
  "pkg-config 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "vcpkg 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -234,12 +234,12 @@ dependencies = [
  "backtrace 0.3.13 (registry+https://github.com/rust-lang/crates.io-index)",
  "chrono 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "curl-sys 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "curl-sys 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "dirs 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "gettext-rs 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gettext-sys 0.19.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
- "libz-sys 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libz-sys 1.0.18 (registry+https://github.com/rust-lang/crates.io-index)",
  "natord 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "nom 4.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "once_cell 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -265,7 +265,7 @@ dependencies = [
 
 [[package]]
 name = "libz-sys"
-version = "1.0.17"
+version = "1.0.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cc 1.0.29 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -863,7 +863,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5067f5bb2d80ef5d68b4c87db81601f0b75bca627bc2ef76b141d7b846a3c6d9"
 "checksum cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "ddfc5b9aa5d4507acaf872de71051dfd0e309860e88966e1051e462a077aac4f"
 "checksum constant_time_eq 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "8ff012e225ce166d4422e0e78419d901719760f62ae2b7969ca6b564d1b54a9e"
-"checksum curl-sys 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)" = "71c63a540a9ee4e15e56c3ed9b11a2f121239b9f6d7b7fe30f616e048148df9a"
+"checksum curl-sys 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)" = "78800a6de442f65dab6ce26c6f369c14fc585686432bf4b77119d2d384216c31"
 "checksum dirs 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "88972de891f6118092b643d85a0b28e0678e0f948d7f879aa32f2d5aafe97d2a"
 "checksum failure 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "795bd83d3abeb9220f257e597aa0080a508b27533824adf336529648f6abf7e2"
 "checksum failure_derive 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "ea1063915fd7ef4309e222a5a07cf9c319fb9c7836b1f89b85458672dbb127e1"
@@ -876,7 +876,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum lazy_static 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "76f033c7ad61445c5b347c7382dd1237847eb1bce590fe50365dcb33d546be73"
 "checksum lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a374c89b9db55895453a74c1e38861d9deec0b01b405a82516e9d5de4820dea1"
 "checksum libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)" = "d515b1f41455adea1313a4a2ac8a8a477634fbae63cc6100e3aebb207ce61558"
-"checksum libz-sys 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)" = "44ebbc760fd2d2f4d93de09a0e13d97e057612052e871da9985cedcb451e6bd5"
+"checksum libz-sys 1.0.18 (registry+https://github.com/rust-lang/crates.io-index)" = "87f737ad6cc6fd6eefe3d9dc5412f1573865bded441300904d2f42269e140f16"
 "checksum locale_config 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "14fbee0e39bc2dd6a2427c4fdea66e9826cc1fd09b0a0b7550359f5f6efe1dab"
 "checksum lock_api 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "62ebf1391f6acad60e5c8b43706dde4582df75c06698ab44511d15016bc2442c"
 "checksum matches 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "7ffc5c5338469d4d3ea17d269fa8ea3512ad247247c30bd2df69e68309ed0a08"
diff --git a/rust/libnewsboat/Cargo.toml b/rust/libnewsboat/Cargo.toml
index 6b9d78dd..5943d43a 100644
--- a/rust/libnewsboat/Cargo.toml
+++ b/rust/libnewsboat/Cargo.toml
@@ -16,14 +16,14 @@ xdg = "2.2.0"
 backtrace = "= 0.3"
 unicode-width = "0.1.5"
 nom = "^4.1"
-curl-sys = "0.4.5"
+curl-sys = "0.4.12"
 libc = "0.2"
 gettext-rs = "0.4.1"
 natord = "1.0.9"
 
 # We don't use the following crates, but we pin their versions to make sure
 # that Newsboat builds with Rust 1.25 and later.
-libz-sys = "= 1.0.17"
+libz-sys = "= 1.0.18"
 
 # The following constraints close security holes
 # https://rustsec.org/advisories/RUSTSEC-2019-0009