diff --git a/deployment/docker/Makefile b/deployment/docker/Makefile
index 9e60a4e3d..de81f30b5 100644
--- a/deployment/docker/Makefile
+++ b/deployment/docker/Makefile
@@ -4,7 +4,7 @@ DOCKER_NAMESPACE := victoriametrics
 
 ROOT_IMAGE ?= alpine:3.12.1
 CERTS_IMAGE := alpine:3.12.1
-GO_BUILDER_IMAGE := golang:1.15.5
+GO_BUILDER_IMAGE := golang:1.15.6
 BUILDER_IMAGE := local/builder:2.0.0-$(shell echo $(GO_BUILDER_IMAGE) | tr : _)
 BASE_IMAGE := local/base:1.1.1-$(shell echo $(ROOT_IMAGE) | tr : _)-$(shell echo $(CERTS_IMAGE) | tr : _)
 
diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index b9550437a..850058157 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -8,6 +8,7 @@
 * FEATURE: add `count_eq_over_time(m[d], N)` and `count_ne_over_time(m[d], N)` for counting the number of samples for `m` over `d` that (equal / not equal) to `N`.
 * FEATURE: do not print usage info for all the command-line flags when incorrect command-line flag is passed. Previously it could be hard reading the error message
   about incorrect command-line flag because of too big usage info for all the flags.
+* FEATURE: upgrade Go builder from v1.15.5 to v1.15.6 . This fixes [issues found in Go since v1.15.5](https://github.com/golang/go/issues?q=milestone%3AGo1.15.6+label%3ACherryPickApproved).
 
 * BUGFIX: properly parse timestamps in OpenMetrics format - they are exposed as floating-point number in seconds instead of integer milliseconds
   unlike in Prometheus exposition format. See [the docs](https://github.com/OpenObservability/OpenMetrics/blob/master/specification/OpenMetrics.md#timestamps).