diff --git a/lib/spack/spack/solver/asp.py b/lib/spack/spack/solver/asp.py
index 75301e3b60d..e9f90ed1136 100644
--- a/lib/spack/spack/solver/asp.py
+++ b/lib/spack/spack/solver/asp.py
@@ -3106,8 +3106,9 @@ def setup(
 
         # abstract specs with commit variants are assigend version most likely to have commit sha
         for spec in specs:
+            commit = spec.variants.get("commit")
             version = spec.versions.concrete_range_as_version
-            if not version:
+            if not version and commit:
                 version = max(spack.repo.PATH.get_pkg_class(spec.fullname).versions.keys())
                 spec.versions = spack.version.VersionList([version])