diff --git a/cfg/posix.cfg b/cfg/posix.cfg
index cc1027d0c..d690bae79 100644
--- a/cfg/posix.cfg
+++ b/cfg/posix.cfg
@@ -366,6 +366,30 @@
       <not-bool/>
     </arg>
   </function>
+  <!-- int openat(int dirfd, const char *pathname, int flags); -->
+  <!-- int openat(int dirfd, const char *pathname, int flags, mode_t mode);  -->
+  <function name="openat">
+    <!-- TODO: add use-retval when cppcheck suppresses redundant messages
+    because of violations to alloc/dealloc and use-retval configuration-->
+    <returnValue type="int"/>
+    <noreturn>false</noreturn>
+    <arg nr="1" direction="in">
+      <valid>0:</valid>
+      <not-uninit/>
+    </arg>
+    <arg nr="2" direction="in">
+      <not-null/>
+      <not-uninit/>
+    </arg>
+    <arg nr="3" direction="in">
+      <not-uninit/>
+      <not-bool/>
+    </arg>
+    <arg nr="4" default="0" direction="in">
+      <not-uninit/>
+      <not-bool/>
+    </arg>
+  </function>
   <!-- int creat(const char *pathname, mode_t mode); -->
   <function name="creat">
     <use-retval/>
@@ -4396,6 +4420,7 @@ The function 'mktemp' is considered to be dangerous due to race conditions and s
   <resource>
     <alloc init="true">open</alloc>
     <alloc init="true">creat</alloc>
+    <alloc init="true">openat</alloc>
     <alloc init="true">socket</alloc>
     <dealloc>close</dealloc>
   </resource>