Merge pull request #403 from BishopFox/fix/dnscrash

Ensure dnsSession is not nil before using it
BishopFox · Apr 21, 2021 · ba43f1d · ba43f1d
2 parents 32a3305 + e4bdad2
commit ba43f1d
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/server/c2/udp-dns.go b/server/c2/udp-dns.go
@@ -627,7 +627,10 @@ func dnsSessionPoll(domain string, fields []string) ([]string, error) {
 		return []string{"1"}, errors.New("invalid session id (session poll)")
 	}
 	dnsSessionsMutex.Lock()
-	dnsSession := (*dnsSessions)[sessionID]
+	dnsSession, found := (*dnsSessions)[sessionID]
+	if !found {
+		return []string{"1"}, errors.New("invalid session (nil pointer")
+	}
 	dnsSessionsMutex.Unlock()
 
 	isDrained := false