diff --git a/SOURCES/RHEL-217923-fix-bundled-pyasn1-CVE-2026-59886.patch b/SOURCES/RHEL-217923-fix-bundled-pyasn1-CVE-2026-59886.patch
new file mode 100644
index 0000000..a096a40
--- /dev/null
+++ b/SOURCES/RHEL-217923-fix-bundled-pyasn1-CVE-2026-59886.patch
@@ -0,0 +1,52 @@
+From e60c691cb91addb8fcefa2f537e85ede6fb1e886 Mon Sep 17 00:00:00 2001
+From: Simon Pichugin <simon.pichugin@gmail.com>
+Date: Wed, 8 Jul 2026 17:32:09 -0700
+Subject: [PATCH] Merge commit from fork
+
+---
+ pyasn1/type/univ.py             | 21 +++++++++----
+ tests/codec/ber/test_decoder.py | 53 +++++++++++++++++++++++++++------
+ tests/codec/cer/test_decoder.py | 10 +++++++
+ tests/codec/der/test_decoder.py | 19 ++++++++++++
+ tests/type/test_univ.py         | 40 +++++++++++++++++++++++++
+ 5 files changed, 129 insertions(+), 14 deletions(-)
+
+diff --git a/kubevirt/pyasn1/type/univ.py b/kubevirt/pyasn1/type/univ.py
+index 9aff5e69..8b786dd9 100644
+--- a/kubevirt/pyasn1/type/univ.py
++++ b/kubevirt/pyasn1/type/univ.py
+@@ -1362,7 +1362,7 @@ class Pi(Real):
+     def __normalizeBase10(value):
+         m, b, e = value
+         while m and m % 10 == 0:
+-            m /= 10
++            m //= 10
+             e += 1
+         return m, b, e
+ 
+@@ -1490,10 +1490,21 @@ def __int__(self):
+     def __float__(self):
+         if self._value in self._inf:
+             return self._value
+-        else:
+-            return float(
+-                self._value[0] * pow(self._value[1], self._value[2])
+-            )
++
++        mantissa, base, exponent = self._value
++
++        if not mantissa:
++            return 0.0
++
++        if base == 2:
++            return math.ldexp(float(mantissa), exponent)
++
++        # base is 10 (prettyIn() rejects everything else); refuse to
++        # materialize astronomically large integers via pow()
++        if exponent > sys.float_info.max_10_exp:
++            raise OverflowError('Real value too large to convert to float')
++
++        return float(mantissa * pow(base, exponent))
+ 
+     def __abs__(self):
+         return self.clone(abs(float(self)))
diff --git a/SPECS/fence-agents.spec b/SPECS/fence-agents.spec
index aa33a21..078bf9a 100644
--- a/SPECS/fence-agents.spec
+++ b/SPECS/fence-agents.spec
@@ -87,7 +87,7 @@
 Name: fence-agents
 Summary: Set of unified programs capable of host isolation ("fencing")
 Version: 4.2.1
-Release: 129%{?alphatag:.%{alphatag}}%{?dist}.28
+Release: 129%{?alphatag:.%{alphatag}}%{?dist}.29
 License: GPLv2+ and LGPLv2+
 Group: System Environment/Base
 URL: https://github.com/ClusterLabs/fence-agents
@@ -339,6 +339,7 @@ Patch1008: RHEL-148156-kubevirt-3-RHEL-146288-fix-bundled-urllib3-CVE-2026-21441
 Patch1009: RHEL-148156-kubevirt-4-RHEL-142447-fix-bundled-pyasn1-CVE-2026-23490.patch
 Patch1010: RHEL-157189-fix-bundled-pyasn1-CVE-2026-30922.patch
 Patch1011: RHEL-178594-kubevirt-fix-bundled-urllib3-CVE-2026-44431.patch
+Patch1012: RHEL-217923-fix-bundled-pyasn1-CVE-2026-59886.patch
 # cloud (x86_64 only)
 Patch2000: bz2218234-2-aws-fix-bundled-dateutil-CVE-2007-4559.patch
 Patch2001: RHEL-43568-2-aws-fix-bundled-urllib3-CVE-2024-37891.patch
@@ -714,6 +715,7 @@ pushd %{buildroot}/usr/lib/fence-agents/%{bundled_lib_dir}
 /usr/bin/patch --no-backup-if-mismatch -p1 --fuzz=0 < %{PATCH1009}
 /usr/bin/patch --no-backup-if-mismatch -p1 --fuzz=2 < %{PATCH1010}
 /usr/bin/patch --no-backup-if-mismatch -p1 --fuzz=0 < %{PATCH1011}
+/usr/bin/patch --no-backup-if-mismatch -p1 --fuzz=0 < %{PATCH1012}
 
 %ifarch x86_64
 /usr/bin/patch --no-backup-if-mismatch -p1 --fuzz=0 < %{PATCH2000}
@@ -1658,6 +1660,10 @@ Fence agent for IBM z/VM over IP.
 %endif
 
 %changelog
+* Thu Jul 30 2026 Oyvind Albrigtsen <oalbrigt@redhat.com> - 4.2.1-129.29
+- bundled pyasn1: fix CVE-2026-59886
+  Resolves: RHEL-217923
+
 * Wed Jul 15 2026 RHEL Packaging Agent <redhat-ymir-agent@redhat.com> - 4.2.1-129.28
 - bundled urllib3: fix CVE-2026-44431
   Resolves: RHEL-178594