diff --git a/go.mod b/go.mod
index 6d59f401cd..916b458517 100644
--- a/go.mod
+++ b/go.mod
@@ -22,7 +22,7 @@ require (
 	github.com/joho/godotenv v1.5.1
 	github.com/jonboulle/clockwork v0.5.0
 	github.com/ktr0731/go-fuzzyfinder v0.9.0
-	github.com/letsencrypt/boulder v0.20260908.0
+	github.com/letsencrypt/boulder v0.20260921.0
 	github.com/mitchellh/go-homedir v1.1.0
 	github.com/pkg/errors v0.9.1
 	github.com/sigstore/sigstore v1.10.9
diff --git a/go.sum b/go.sum
index edfc1d6536..f6792b4dfd 100644
--- a/go.sum
+++ b/go.sum
@@ -323,8 +323,8 @@ github.com/ktr0731/go-fuzzyfinder v0.9.0 h1:JV8S118RABzRl3Lh/RsPhXReJWc2q0rbuipz
 github.com/ktr0731/go-fuzzyfinder v0.9.0/go.mod h1:uybx+5PZFCgMCSDHJDQ9M3nNKx/vccPmGffsXPn2ad8=
 github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0SNc=
 github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
-github.com/letsencrypt/boulder v0.20260908.0 h1:vs74OyVm0tX3BT4cKyuk0ovQvC5ptuaLbvLfXiW7mDU=
-github.com/letsencrypt/boulder v0.20260908.0/go.mod h1:KViRlE3VxbUbyh3mtzOE7o2zV2QelFUjSg+X9CHPP6U=
+github.com/letsencrypt/boulder v0.20260921.0 h1:+7JY/LLJvE0blqELblgP63FOwkE94+udD/5483HeHpE=
+github.com/letsencrypt/boulder v0.20260921.0/go.mod h1:KViRlE3VxbUbyh3mtzOE7o2zV2QelFUjSg+X9CHPP6U=
 github.com/liggitt/tabwriter v0.0.0-20181228230101-89fcab3d43de h1:9TO3cAIGXtEhnIaL+V+BEER86oLrvS+kWobKpbJuye0=
 github.com/liggitt/tabwriter v0.0.0-20181228230101-89fcab3d43de/go.mod h1:zAbeS9B/r2mtpb6U+EI2rYA5OAXxsYw6wTamcNW+zcE=
 github.com/lucasb-eyer/go-colorful v1.4.0 h1:UtrWVfLdarDgc44HcS7pYloGHJUjHV/4FwW4TvVgFr4=
diff --git a/vendor/modules.txt b/vendor/modules.txt
index 73600e11e3..063d755423 100644
--- a/vendor/modules.txt
+++ b/vendor/modules.txt
@@ -366,7 +366,7 @@ github.com/ktr0731/go-ansisgr
 github.com/ktr0731/go-fuzzyfinder
 github.com/ktr0731/go-fuzzyfinder/matching
 github.com/ktr0731/go-fuzzyfinder/scoring
-# github.com/letsencrypt/boulder v0.20260908.0
+# github.com/letsencrypt/boulder v0.20260921.0
 ## explicit; go 1.26.0
 github.com/letsencrypt/boulder/core
 github.com/letsencrypt/boulder/core/proto