diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4fffdf0c..bbcf4532 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -52,6 +52,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Fix the issue that new files created with wwctl overlay edit have 755 permissions. #1236
 - Mount `/sys` and `/run` during `wwctl container exec`. #1287
 
+### Changed
+
+- Explicitly ignore compat-style NIS lines in passwd/group during syncuser. #1286
+
 ## v4.5.4, 2024-06-12
 
 ### Fixed
diff --git a/internal/pkg/container/syncuids.go b/internal/pkg/container/syncuids.go
index 211567e7..7bb19153 100644
--- a/internal/pkg/container/syncuids.go
+++ b/internal/pkg/container/syncuids.go
@@ -176,13 +176,16 @@ func (db syncDB) read(fileName string, fromContainer bool) error {
 			if name == "" {
 				continue
 			}
-
+			// ignore ldap/nis/sssd line
+			if strings.HasPrefix(fields[0], "+") || strings.HasPrefix(fields[0], "-") {
+				wwlog.Verbose("Ignoring line %s (unhandled compat-style NIS reference)", line)
+				continue
+			}
 			id, err := strconv.Atoi(fields[2])
 			if err != nil {
 				wwlog.Warn("Ignoring line %s (parse error)", line)
 				continue
 			}
-
 			entry, ok := db[name]
 			if !ok {
 				entry = syncInfo{HostID: -1, ContainerID: -1}
diff --git a/internal/pkg/container/syncuids_test.go b/internal/pkg/container/syncuids_test.go
index abaad68a..efd3c6f3 100644
--- a/internal/pkg/container/syncuids_test.go
+++ b/internal/pkg/container/syncuids_test.go
@@ -1,10 +1,12 @@
 package container
 
 import (
+	"bytes"
 	"os"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/warewulf/warewulf/internal/pkg/wwlog"
 )
 
 func writeTempFile(t *testing.T, input string) string {
@@ -268,3 +270,18 @@ func Test_malformed_passwd(t *testing.T) {
 	err := db.readFromHost(hostFileName)
 	assert.NoError(t, err)
 }
+
+func Test_network_passwd(t *testing.T) {
+	buf := new(bytes.Buffer)
+	wwlog.SetLogWriter(buf)
+	hostInput := `testuser1:x:1001:1001::/home/testuser:/bin/bash
++::::::
+-::::::`
+	hostFileName := writeTempFile(t, hostInput)
+	defer os.Remove(hostFileName)
+	db := make(syncDB)
+	err := db.readFromHost(hostFileName)
+	assert.NotContains(t, buf.String(), "parse error")
+	assert.Contains(t, buf.String(), "Ignoring line")
+	assert.NoError(t, err)
+}