Copyright © 2012 Red Hat, Inc. All rights reserved. Important 2026-07-14T16:38:29 pyasn1: pyasn1: Denial of Service via crafted ASN.1 REAL values 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CWE-770

pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.4, the univ.Real type converted its mantissa, base, and exponent value to a Python float using exact big-integer exponentiation. A BER, CER, or DER encoded REAL value only a few bytes long can carry a very large exponent, causing float conversion through prettyPrint(), str(), comparison, arithmetic, int(), or an explicit float() call to consume excessive CPU and memory and hang applications that decode untrusted ASN.1 data and then print, log, or compare decoded objects. This issue is fixed in version 0.6.4.

A remote attacker can exploit this by providing specially crafted BER/CER/DER-encoded ASN.1 data with a large exponent in the REAL value. When the application subsequently prints, logs, compares, or performs arithmetic on the decoded value, this can cause excessive CPU and memory consumption, leading to a denial of service (DoS).

This flaw in pyasn1, rated as Important, could lead to a denial of service in Red Hat products that process untrusted ASN.1 data. A remote attacker could send a specially crafted BER, CER, or DER encoded REAL value with a large exponent, causing applications to consume excessive resources during decoding operations such as printing, logging, or arithmetic, thereby rendering the service unavailable. When processing untrusted ASN.1 data with pyasn1, avoid calling prettyPrint(), str(), float(), int(), or performing comparisons or arithmetic on decoded Real (ASN.1 REAL type) objects. Instead, inspect the raw (mantissa, base, exponent) tuple directly. Where logging decoded ASN.1 structures is necessary, filter out or sanitize Real-typed values before conversion. Red Hat Hardened Images 2026-07-09T00:00:00Z RHSA-2026:37094 mariadb11-8-main-11.8.8-3.hum1 Exploit Intelligence Under investigation exploit-intelligence-tech-preview/vulnerability-analysis-rhel9 Lightspeed Core Affected lightspeed-core/lightspeed-stack-rhel9 Migration Toolkit for Applications 8 Affected mta/mta-rhel9-operator Migration Toolkit for Applications 8 Affected mta/mta-solution-server-rhel9 Migration Toolkit for Containers Affected rhmtc/openshift-migration-rhel8-operator Migration Toolkit for Virtualization Affected migration-toolkit-virtualization/mtv-rhel9-operator Migration Toolkit for Virtualization Will not fix mtv-candidate/mtv-rhel9-operator OpenShift Lightspeed Affected openshift-lightspeed/lightspeed-agentic-sandbox-rhel9 OpenShift Lightspeed Affected openshift-lightspeed/lightspeed-service-api-rhel9 OpenShift Lightspeed Affected openshift-lightspeed/lightspeed-to-dataverse-exporter-rhel9 OpenShift Service Mesh 3 Not affected openshift-service-mesh/kiali-rhel9-operator Red Hat Advanced Cluster Management for Kubernetes 2 Will not fix rhacm2/volsync-operator-bundle Red Hat Advanced Cluster Management for Kubernetes 2 Will not fix rhacm2/volsync-rhel9 Red Hat AI Inference Server Affected rhaiis/vllm-rocm-rhel9 Red Hat AI Inference Server Will not fix rhaiis/vllm-tpu-rhel9 Red Hat AI Inference Server Affected rhaii/vllm-rocm-rhel9 Red Hat AI Inference Server Will not fix rhaii/vllm-tpu-rhel9 Red Hat Ansible Automation Platform 2 Under investigation ansible-automation-platform-24/ee-minimal-rhel8 Red Hat Ansible Automation Platform 2 Under investigation ansible-automation-platform-24/ee-minimal-rhel9 Red Hat Ansible Automation Platform 2 Under investigation ansible-automation-platform-24/ee-supported-rhel8 Red Hat Ansible Automation Platform 2 Under investigation ansible-automation-platform-24/ee-supported-rhel9 Red Hat Ansible Automation Platform 2 Under investigation ansible-automation-platform-24/lightspeed-rhel8 Red Hat Ansible Automation Platform 2 Under investigation ansible-automation-platform-24/platform-resource-runner-rhel8 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-25/ee-supported-rhel8 Red Hat Ansible Automation Platform 2 Will not fix ansible-automation-platform-25/lightspeed-chatbot-rhel8 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-25/lightspeed-rhel8 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-26/controller-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-26/controller-rhel9-operator Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-26/eda-controller-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-26/eda-controller-rhel9-operator Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-26/ee-supported-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-26/gateway-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-26/gateway-rhel9-operator Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-26/hub-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-26/hub-rhel9-operator Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-26/lightspeed-chatbot-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-26/lightspeed-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-26/lightspeed-rhel9-operator Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-26/platform-resource-rhel9-operator Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/aap-cloud-billing-operator-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/controller-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/controller-rhel9-operator Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/eda-controller-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/eda-controller-rhel9-operator Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/ee-supported-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/gateway-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/gateway-rhel9-operator Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/hub-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/hub-rhel9-operator Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/lightspeed-chatbot-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/lightspeed-rhel9 Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/lightspeed-rhel9-operator Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/metrics-service-rhel9-operator Red Hat Ansible Automation Platform 2 Affected ansible-automation-platform-27/platform-resource-rhel9-operator Red Hat Ansible Automation Platform 2 Under investigation ansible-automation-platform-tech-preview/metrics-service-rhel9-operator Red Hat Ansible Automation Platform 2 Affected automation-controller Red Hat Ansible Automation Platform 2 Under investigation python3.11-pyasn1 Red Hat Ansible Automation Platform 2 Under investigation python3.11-pyasn1-modules Red Hat Ansible Automation Platform 2 Affected python3.12-pyasn1 Red Hat Ansible Automation Platform 2 Not affected python3.12-pyasn1-modules Red Hat Ansible Automation Platform 2 Under investigation python3x-pyasn1 Red Hat Ceph Storage 7 Affected rhceph/rhceph-7-rhel9 Red Hat Ceph Storage 8 Affected rhceph/rhceph-8-rhel9 Red Hat Ceph Storage 9 Affected rhceph/rhceph-9-rhel9 Red Hat Enterprise Linux 10 Under investigation fence-agents Red Hat Enterprise Linux 10 Under investigation python-pyasn1 Red Hat Enterprise Linux 10 Under investigation rhel10/keylime-registrar Red Hat Enterprise Linux 10 Under investigation rhel10/keylime-verifier Red Hat Enterprise Linux 6 Out of support scope python-pyasn1 Red Hat Enterprise Linux 7 Under investigation python-pyasn1 Red Hat Enterprise Linux 7 Under investigation resource-agents Red Hat Enterprise Linux 8 Under investigation fence-agents Red Hat Enterprise Linux 8 Under investigation python-pyasn1 Red Hat Enterprise Linux 8 Under investigation resource-agents Red Hat Enterprise Linux 9 Under investigation fence-agents Red Hat Enterprise Linux 9 Under investigation python-pyasn1 Red Hat Enterprise Linux 9 Under investigation rhel9/keylime-registrar Red Hat Enterprise Linux 9 Under investigation rhel9/keylime-verifier Red Hat Enterprise Linux AI (RHEL AI) 3 Affected rhelai3/bootc-azure-cuda-rhel9 Red Hat Enterprise Linux AI (RHEL AI) 3 Affected rhelai3/bootc-azure-rocm-rhel9 Red Hat Enterprise Linux AI (RHEL AI) 3 Affected rhelai3/bootc-rocm-rhel9 Red Hat Hardened Images Affected jaeger Red Hat Hardened Images Not affected llvm Red Hat Hardened Images Affected python-trustme Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-feature-server-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-kserve-agent-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-kserve-controller-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-kserve-router-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-kserve-storage-initializer-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-llama-stack-core-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-mlflow-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-ml-pipelines-runtime-generic-rhel9 Red Hat OpenShift AI (RHOAI) Not affected rhoai/odh-model-registry-job-async-upload-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-pipeline-runtime-datascience-cpu-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-pipeline-runtime-pytorch-cuda-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-pipeline-runtime-pytorch-llmcompressor-cuda-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-pipeline-runtime-pytorch-rocm-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-pipeline-runtime-tensorflow-cuda-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-pipeline-runtime-tensorflow-rocm-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-pipelines-components-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-th06-cpu-torch210-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-th06-cuda130-torch210-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-th06-rocm64-torch291-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-training-cuda128-torch29-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-trustyai-garak-lls-provider-dsp-rhel9 Red Hat OpenShift AI (RHOAI) Not affected rhoai/odh-trustyai-nemo-guardrails-server-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-workbench-codeserver-datascience-cpu-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-workbench-jupyter-datascience-cpu-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-workbench-jupyter-pytorch-cuda-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-workbench-jupyter-pytorch-llmcompressor-cuda-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-workbench-jupyter-pytorch-rocm-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-workbench-jupyter-tensorflow-cuda-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-workbench-jupyter-tensorflow-rocm-py312-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-workbench-jupyter-trustyai-cpu-py312-rhel9 Red Hat OpenShift Container Platform 4 Affected openshift4/ose-ansible-rhel9-operator Red Hat OpenShift Container Platform 4 Affected python-pyasn1 Red Hat OpenStack Platform 16.2 Under investigation python-pyasn1 Red Hat OpenStack Platform 17.1 Under investigation python-pyasn1 Red Hat OpenStack Platform 18.0 Under investigation rhoso-operators/ee-openstack-ansible-ee-rhel9 Red Hat Quay 3 Affected quay/quay-rhel8 Red Hat Quay 3 Affected quay/quay-rhel9 Red Hat Satellite 6 Under investigation python3.12-pyasn1 Red Hat Satellite 6 Under investigation python3.12-pyasn1-modules Red Hat Satellite 6 Under investigation python-pyasn1 Red Hat Satellite 6 Under investigation python-pyasn1-modules Red Hat Satellite 6 Under investigation satellite/iop-advisor-backend-rhel9 Red Hat Satellite 6 Under investigation satellite/iop-advisor-engine-rhel9 Red Hat Trusted Artifact Signer Affected rhtas/model-transparency-rhel9 Red Hat Trusted Artifact Signer Affected rhtas/segment-reporting-rhel9 Service Telemetry Framework 1.5 Under investigation stf/prometheus-webhook-snmp-rhel9 Service Telemetry Framework 1.5 Under investigation stf/service-telemetry-rhel9-operator Service Telemetry Framework 1.5 Under investigation stf/smart-gateway-rhel9-operator https://www.cve.org/CVERecord?id=CVE-2026-59886 https://nvd.nist.gov/vuln/detail/CVE-2026-59886 https://github.com/pyasn1/pyasn1/commit/e60c691cb91addb8fcefa2f537e85ede6fb1e886 https://github.com/pyasn1/pyasn1/releases/tag/v0.6.4 https://github.com/pyasn1/pyasn1/security/advisories/GHSA-hm4w-wwcw-mr6r