diff --git a/go.mod b/go.mod
index 1ae406d2c0..2a9a269711 100644
--- a/go.mod
+++ b/go.mod
@@ -25,10 +25,10 @@ require (
 	k8s.io/apimachinery v0.28.5
 	k8s.io/client-go v0.28.5
 	k8s.io/utils v0.0.0-20230406110748-d93618cff8a2
-	knative.dev/eventing v0.40.1-0.20240201205049-d258e7dd535c
+	knative.dev/eventing v0.40.1-0.20240202144010-469d0ac85e86
 	knative.dev/hack v0.0.0-20240201013652-f3881d90c189
 	knative.dev/pkg v0.0.0-20240201013110-e85c3cf6d5f1
-	knative.dev/reconciler-test v0.0.0-20240201013705-feb27a771d67
+	knative.dev/reconciler-test v0.0.0-20240202062219-3bf004cddd5c
 	sigs.k8s.io/yaml v1.4.0
 )
 
diff --git a/go.sum b/go.sum
index a4c8dd3c55..4ec72f1fc5 100644
--- a/go.sum
+++ b/go.sum
@@ -970,14 +970,14 @@ k8s.io/kube-openapi v0.0.0-20230717233707-2695361300d9 h1:LyMgNKD2P8Wn1iAwQU5Ohx
 k8s.io/kube-openapi v0.0.0-20230717233707-2695361300d9/go.mod h1:wZK2AVp1uHCp4VamDVgBP2COHZjqD1T68Rf0CM3YjSM=
 k8s.io/utils v0.0.0-20230406110748-d93618cff8a2 h1:qY1Ad8PODbnymg2pRbkyMT/ylpTrCM8P2RJ0yroCyIk=
 k8s.io/utils v0.0.0-20230406110748-d93618cff8a2/go.mod h1:OLgZIPagt7ERELqWJFomSt595RzquPNLL48iOWgYOg0=
-knative.dev/eventing v0.40.1-0.20240201205049-d258e7dd535c h1:/HxlmvJpSqwyZRk2xjType+BI3C/1rB7Mpbi7AKRn3I=
-knative.dev/eventing v0.40.1-0.20240201205049-d258e7dd535c/go.mod h1:B3/ep06tqwcAfcH7R5eGKi7bgZTfqb59MPoqfV8Jirg=
+knative.dev/eventing v0.40.1-0.20240202144010-469d0ac85e86 h1:a+k1iy7L+AQPY0jbWWM+7N6h5DXvvNw3L0f9cN60WKo=
+knative.dev/eventing v0.40.1-0.20240202144010-469d0ac85e86/go.mod h1:gji5GMsP3ahX6Ul5y/rqp6X2oNTurLwdekzl6Tt16zo=
 knative.dev/hack v0.0.0-20240201013652-f3881d90c189 h1:a8htyuf5+S0NGxxdKXeQ49XOD9dEC1LHoofRQPgFKrU=
 knative.dev/hack v0.0.0-20240201013652-f3881d90c189/go.mod h1:yk2OjGDsbEnQjfxdm0/HJKS2WqTLEFg/N6nUs6Rqx3Q=
 knative.dev/pkg v0.0.0-20240201013110-e85c3cf6d5f1 h1:xGmWQyA+hwyFT1BN5RWi8wx0DxwZQZni8SPN/FZ02kI=
 knative.dev/pkg v0.0.0-20240201013110-e85c3cf6d5f1/go.mod h1:cGCJe6wkr0vQMAXTaUHi0XA/12JbxSTK15TnyBmn7ms=
-knative.dev/reconciler-test v0.0.0-20240201013705-feb27a771d67 h1:cgAtVlJJaWRBM5MzuN7ig++Z61FO5j2EoAqRBITSLRw=
-knative.dev/reconciler-test v0.0.0-20240201013705-feb27a771d67/go.mod h1:GYf5f0+DBK7736Y9VydjMkmkCqbWKIlRWN+SQ5tJ7A0=
+knative.dev/reconciler-test v0.0.0-20240202062219-3bf004cddd5c h1:UYcWk9LGRjxvlx0AFKPTm8YWqxNstFxF++zyIZK6TnE=
+knative.dev/reconciler-test v0.0.0-20240202062219-3bf004cddd5c/go.mod h1:GYf5f0+DBK7736Y9VydjMkmkCqbWKIlRWN+SQ5tJ7A0=
 pgregory.net/rapid v0.3.3/go.mod h1:UYpPVyjFHzYBGHIxLFoupi8vwk6rXNzRY9OMvVxFIOU=
 pgregory.net/rapid v1.1.0 h1:CMa0sjHSru3puNx+J0MIAuiiEV4N0qj8/cMWGBBCsjw=
 pgregory.net/rapid v1.1.0/go.mod h1:PY5XlDGj0+V1FCq0o192FdRhpKHGTRIWBgqjDBTrq04=
diff --git a/vendor/knative.dev/reconciler-test/pkg/eventshub/assert/step.go b/vendor/knative.dev/reconciler-test/pkg/eventshub/assert/step.go
index 2bbff311c5..21464fc8a5 100644
--- a/vendor/knative.dev/reconciler-test/pkg/eventshub/assert/step.go
+++ b/vendor/knative.dev/reconciler-test/pkg/eventshub/assert/step.go
@@ -1,8 +1,10 @@
 package assert
 
 import (
+	"bytes"
 	"context"
 	"encoding/json"
+	"encoding/pem"
 	"fmt"
 
 	cetest "github.com/cloudevents/sdk-go/v2/test"
@@ -144,13 +146,40 @@ func MatchPeerCertificatesFromSecret(namespace, name string, key string) eventsh
 			return fmt.Errorf("failed to match peer certificates, connection is not TLS")
 		}
 
-		for _, cert := range info.Connection.TLS.PemPeerCertificates {
-			if cert == string(value) {
-				return nil
+		// secret value can, in general, be a certificate chain (a sequence of PEM-encoded certificate blocks)
+		valueBlock, valueRest := pem.Decode(value)
+		if valueBlock == nil {
+			// error if there's not even a single certificate in the value
+			return fmt.Errorf("failed to decode secret certificate:\n%s", string(value))
+		}
+		// for each certificate in the chain, check if it's present in info.Connection.TLS.PemPeerCertificates
+		for valueBlock != nil {
+			found := false
+			for _, cert := range info.Connection.TLS.PemPeerCertificates {
+				certBlock, _ := pem.Decode([]byte(cert))
+				if certBlock == nil {
+					return fmt.Errorf("failed to decode peer certificate:\n%s", cert)
+				}
+
+				if certBlock.Type == valueBlock.Type && string(certBlock.Bytes) == string(valueBlock.Bytes) {
+					found = true
+					break
+				}
+			}
+
+			if !found {
+				pemBytes, _ := json.MarshalIndent(info.Connection.TLS.PemPeerCertificates, "", "  ")
+				return fmt.Errorf("failed to find peer certificate with value\n%s\nin:\n%s", string(value), string(pemBytes))
 			}
+
+			valueBlock, valueRest = pem.Decode(valueRest)
+		}
+
+		// any non-whitespace suffix not parsed as a PEM is suspicious, so we treat it as an error:
+		if "" != string(bytes.TrimSpace(valueRest)) {
+			return fmt.Errorf("failed to decode secret certificate starting with\n%s\nin:\n%s", string(valueRest), string(value))
 		}
 
-		bytes, _ := json.MarshalIndent(info.Connection.TLS.PemPeerCertificates, "", "  ")
-		return fmt.Errorf("failed to find peer certificate with value\n%s\nin:\n%s", string(value), string(bytes))
+		return nil
 	}
 }
diff --git a/vendor/modules.txt b/vendor/modules.txt
index 99f4d3e8d6..e8cac572ee 100644
--- a/vendor/modules.txt
+++ b/vendor/modules.txt
@@ -1304,7 +1304,7 @@ k8s.io/utils/net
 k8s.io/utils/pointer
 k8s.io/utils/strings/slices
 k8s.io/utils/trace
-# knative.dev/eventing v0.40.1-0.20240201205049-d258e7dd535c
+# knative.dev/eventing v0.40.1-0.20240202144010-469d0ac85e86
 ## explicit; go 1.21
 knative.dev/eventing/cmd/heartbeats
 knative.dev/eventing/pkg/adapter/v2
@@ -1520,7 +1520,7 @@ knative.dev/pkg/webhook/resourcesemantics
 knative.dev/pkg/webhook/resourcesemantics/conversion
 knative.dev/pkg/webhook/resourcesemantics/defaulting
 knative.dev/pkg/webhook/resourcesemantics/validation
-# knative.dev/reconciler-test v0.0.0-20240201013705-feb27a771d67
+# knative.dev/reconciler-test v0.0.0-20240202062219-3bf004cddd5c
 ## explicit; go 1.21
 knative.dev/reconciler-test/cmd/eventshub
 knative.dev/reconciler-test/pkg/environment