CVE-2026-119196
Description
A flaw was found in pyasn1. A remote attacker can cause a Denial of Service (DoS) by sending specially crafted Abstract Syntax Notation One (ASN.1) data containing multiple constructed bit string fragments. When decoding these fragments, the library repeatedly copies and shifts accumulated bit data, leading to quadratic processing time and excessive CPU consumption.
Statement
Red Hat has classified this vulnerability as Important because an unauthenticated network attacker can cause CPU starvation and worker thread exhaustion across network-exposed services without requiring elevated privileges. Within Red Hat distributions and enterprise platforms, pyasn1 serves as an underlying ASN.1 parsing library for several automation components, identity management services, and containerized workloads. Although client-side and internal utilities experience negligible operational risk, network-facing services that ingest untrusted or schema-less ASN.1 structures are directly exposed to availability denial.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | 7.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
When allocating resources without limits, an attacker could prevent other systems, applications, or processes from accessing the same type of resource. It can be easy for an attacker to consume many resources by rapidly making many requests or causing larger resources to be used than is needed.
Frequently Asked Questions
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