diff --git a/Cargo.lock b/Cargo.lock
index 5af288d43..6d3931735 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -54,9 +54,9 @@ checksum = "7b7e4c2464d97fe331d41de9d5db0def0a96f4d823b8b32a2efd503578988973"
 
 [[package]]
 name = "base64"
-version = "0.21.6"
+version = "0.21.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c79fed4cdb43e993fcdadc7e58a09fd0e3e649c4436fa11da71c9f1f3ee7feb9"
+checksum = "9d297deb1925b89f2ccc13d7635fa0714f12c87adce1c75356b39ca9b7178567"
 
 [[package]]
 name = "bitflags"
diff --git a/Cargo.toml b/Cargo.toml
index bbb894fc9..523525972 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -37,7 +37,7 @@ thiserror = "1.0"
 
 [dev-dependencies]
 assert_matches = "1.5.0"
-base64 = "0.21.6"
+base64 = "0.21.7"
 cfg-if = "1.0.0"
 criterion = "0.5"
 fixed-macro = "1.2.0"
diff --git a/binaries/Cargo.toml b/binaries/Cargo.toml
index 87c78a18a..fbabc7b10 100644
--- a/binaries/Cargo.toml
+++ b/binaries/Cargo.toml
@@ -7,7 +7,7 @@ license = "MPL-2.0"
 repository = "https://github.com/divviup/libprio-rs"
 
 [dependencies]
-base64 = "0.21.6"
+base64 = "0.21.7"
 fixed = "1.23"
 fixed-macro = "1.2.0"
 prio = { path = "..", features = ["experimental"] }
diff --git a/supply-chain/audits.toml b/supply-chain/audits.toml
index 0032ef2da..ba10cb544 100644
--- a/supply-chain/audits.toml
+++ b/supply-chain/audits.toml
@@ -76,6 +76,11 @@ criteria = "safe-to-run"
 delta = "0.21.5 -> 0.21.6"
 notes = "sourcegraph-based diff did not see the v0.21.6 tag; I retrieved a local copy of the repo and used that for diff'ing."
 
+[[audits.base64]]
+who = "David Cook <dcook@divviup.org>"
+criteria = "safe-to-run"
+delta = "0.21.6 -> 0.21.7"
+
 [[audits.block-buffer]]
 who = "David Cook <dcook@divviup.org>"
 criteria = "safe-to-deploy"