diff --git a/security/manager/ssl/crypto_hash/Cargo.toml b/security/manager/ssl/crypto_hash/Cargo.toml
index f842368d4b5f2..7b7cfa2ef48dd 100644
--- a/security/manager/ssl/crypto_hash/Cargo.toml
+++ b/security/manager/ssl/crypto_hash/Cargo.toml
@@ -11,5 +11,13 @@ md-5 = "0.10.2"
 nserror = { path = "../../../../xpcom/rust/nserror" }
 nsstring = { path = "../../../../xpcom/rust/nsstring" }
 sha1 = "0.10.2"
-sha2 = "0.10.2"
 xpcom = { path = "../../../../xpcom/rust/xpcom" }
+
+# bug 1838108: on Windows 7 pre-SP1, AVX instructions are disabled, even though
+# they might be supported by the processor. cpufeatures doesn't take this into
+# account, so the assembly implementation causes illegal instruction crashes.
+# As a workaround for now, use the non-assembly implementation.
+[target.'cfg(windows)'.dependencies]
+sha2 = { version = "0.10.2", features = ["force-soft"]}
+[target.'cfg(not(windows))'.dependencies]
+sha2 = "0.10.2"
\ No newline at end of file