Cyber Resilience

CVE-2023-36843

Juniper Junos ≤ 20.4

Published
12 October 2023
Modified
21 November 2024
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0055 43th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2023-36843 is a high-severity Improper Handling of Inconsistent Special Elements (CWE-168) vulnerability in Juniper Junos. Its CVSS base score is 7.5 (High).

Operationally, ranked at the 43th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability Data

An Improper Handling of Inconsistent Special Elements vulnerability in the Junos Services Framework (jsf) module of Juniper Networks Junos OS allows an unauthenticated network based attacker to cause a crash in the Packet Forwarding Engine (pfe) and thereby resulting in…

more

a Denial of Service (DoS). Upon receiving malformed SSL traffic, the PFE crashes. A manual restart will be needed to recover the device. This issue only affects devices with Juniper Networks Advanced Threat Prevention (ATP) Cloud enabled with Encrypted Traffic Insights (configured via ‘security-metadata-streaming policy’). This issue affects Juniper Networks Junos OS: * All versions prior to 20.4R3-S8, 20.4R3-S9; * 21.1 version 21.1R1 and later versions; * 21.2 versions prior to 21.2R3-S6; * 21.3 versions prior to 21.3R3-S5; * 21.4 versions prior to 21.4R3-S5; * 22.1 versions prior to 22.1R3-S4; * 22.2 versions prior to 22.2R3-S2; * 22.3 versions prior to 22.3R2-S2, 22.3R3; * 22.4 versions prior to 22.4R2-S1, 22.4R3;

CWE(s)

Related Threats

CVEs Like This One

CVE-2023-44188Same product: Juniper Junos
CVE-2023-28975Same product: Juniper Junos
CVE-2023-22391Same product: Juniper Junos
CVE-2024-39511Same product: Juniper Junos
CVE-2024-47494Same product: Juniper Junos
CVE-2026-21916Same product: Juniper Junos
CVE-2025-21601Same product: Juniper Junos
CVE-2023-22399Same product: Juniper Junos
CVE-2024-21601Same product: Juniper Junos
CVE-2023-28979Same product: Juniper Junos

Affected Assets

juniper
junos
20.4, 21.1, 21.2, 21.3, 21.4 · ≤ 20.4

Mitigating Controls

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require robust input parsing and validation to avoid inconsistent special-element handling.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Security testing can detect inconsistent-element flaws but does not prevent them by itself.

prevents

Secure development lifecycle includes input-handling requirements that can prevent inconsistent special-element issues.

prevents

Application security requirements typically mandate robust input validation and sanitization.

prevents

Secure architecture principles encourage consistent data handling but do not directly address this weakness.

prevents

Secure coding standards explicitly require proper handling of special characters and reserved words.

References