diff --git a/.cirrus.yml b/.cirrus.yml
index 54458bfd38..e159dbb0ac 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -397,6 +397,8 @@ asan_sanitizer_task:
     CXXFLAGS: -DZEEK_DICT_DEBUG
     ZEEK_CI_CONFIGURE_FLAGS: *ASAN_SANITIZER_CONFIG
     ASAN_OPTIONS: detect_leaks=1:detect_odr_violation=0
+    # Use absolute paths for coverage files.
+    CCACHE_BASEDIR:
 
 ubsan_sanitizer_task:
   container: