diff --git a/Cargo.lock b/Cargo.lock
index 670fa19..15e6547 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2536,7 +2536,7 @@ name = "praxis-policy-plugin-delegator-oauth"
 version = "0.1.0"
 dependencies = [
  "async-trait",
- "base64 0.22.1",
+ "base64 0.23.1",
  "bytes",
  "chrono",
  "getrandom 0.4.3",
@@ -2556,7 +2556,7 @@ name = "praxis-policy-plugin-elicitation-ciba"
 version = "0.1.0"
 dependencies = [
  "async-trait",
- "base64 0.22.1",
+ "base64 0.23.1",
  "chrono",
  "praxis-policy-core",
  "serde",
@@ -2570,7 +2570,7 @@ name = "praxis-policy-plugin-identity-jwt"
 version = "0.1.0"
 dependencies = [
  "async-trait",
- "base64 0.22.1",
+ "base64 0.23.1",
  "chrono",
  "futures",
  "jsonwebtoken",
diff --git a/builtins/plugins/delegator-oauth/Cargo.toml b/builtins/plugins/delegator-oauth/Cargo.toml
index da6773b..3818729 100644
--- a/builtins/plugins/delegator-oauth/Cargo.toml
+++ b/builtins/plugins/delegator-oauth/Cargo.toml
@@ -54,7 +54,7 @@ tracing = { workspace = true }
 # read-only interop check (did the IdP honor the RFC 8693 `actor_token`
 # and emit an `act` claim). We never verify the signature here — the
 # token is already trusted, having just come from our own IdP roundtrip.
-base64 = "0.22"
+base64 = "0.23"
 
 # Secret-clearing wrapper for client credentials in memory.
 zeroize = { version = "1.9", features = ["zeroize_derive"] }
diff --git a/builtins/plugins/elicitation-ciba/Cargo.toml b/builtins/plugins/elicitation-ciba/Cargo.toml
index 19768cb..75ecbb9 100644
--- a/builtins/plugins/elicitation-ciba/Cargo.toml
+++ b/builtins/plugins/elicitation-ciba/Cargo.toml
@@ -43,7 +43,7 @@ praxis-policy-core = { workspace = true }
 
 # `base64` to decode the JWT payload segment for the approver claim
 # (claims extraction only — see the validate notes in approver.rs).
-base64 = "0.22"
+base64 = "0.23"
 
 async-trait = { workspace = true }
 serde = { workspace = true }
diff --git a/builtins/plugins/identity-jwt/Cargo.toml b/builtins/plugins/identity-jwt/Cargo.toml
index 07d25ca..4ec9e20 100644
--- a/builtins/plugins/identity-jwt/Cargo.toml
+++ b/builtins/plugins/identity-jwt/Cargo.toml
@@ -45,7 +45,7 @@ jsonwebtoken = { version = "11", features = ["aws_lc_rs"] }
 # `base64` for the peek-at-iss helper (split + URL_SAFE_NO_PAD decode
 # of the middle JWT segment). Pinned to 0.22 to match what
 # jsonwebtoken pulls — Cargo dedups to a single version.
-base64 = "0.22"
+base64 = "0.23"
 
 # `chrono` for the `resolved_at` timestamp on IdentityPayload. Comes
 # in transitively via praxis-policy-core already; redeclaring keeps the