Cyber Resilience

CVE-2023-22391

Juniper Junos ≤ 19.4

Published
13 January 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 0.0062 46th percentile
Risk Priority 58 floored blend · peak EPSS

Summary

CVE-2023-22391 is a high-severity Improper Handling of Exceptional Conditions (CWE-755) vulnerability in Juniper Junos. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Client Execution (T1203); ranked at the 46th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A vulnerability in class-of-service (CoS) queue management in Juniper Networks Junos OS on the ACX2K Series devices allows an unauthenticated network-based attacker to cause a Denial of Service (DoS). Specific packets are being incorrectly routed to a queue used for…

more

other high-priority traffic such as BGP, PIM, ICMP, ICMPV6 ND and ISAKMP. Due to this misclassification of traffic, receipt of a high rate of these specific packets will cause delays in the processing of other traffic, leading to a Denial of Service (DoS). Continued receipt of this amount of traffic will create a sustained Denial of Service (DoS) condition. This issue affects Juniper Networks Junos OS on ACX2K Series: All versions prior to 19.4R3-S9; All 20.2 versions; 20.3 versions prior to 20.3R3-S6 on ACX2K Series; 20.4 versions prior to 20.4R3-S4 on ACX2K Series; All 21.1 versions; 21.2 versions prior to 21.2R3-S3 on ACX2K Series. Note: This issues affects legacy ACX2K Series PPC-based devices. This platform reached Last Supported Version (LSV) as of the Junos OS 21.2 Release.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1489 Service Stop Impact
Adversaries may stop or disable services on a system to render those services unavailable to legitimate users.
T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-52948Same product: Juniper Junos
CVE-2026-0203Same product: Juniper Junos
CVE-2025-21602Same product: Juniper Junos
CVE-2024-39552Same product: Juniper Junos
CVE-2024-21585Same product: Juniper Junos
CVE-2024-39541Same product: Juniper Junos
CVE-2024-39525Same product: Juniper Junos
CVE-2024-30380Same product: Juniper Junos
CVE-2025-30652Same product: Juniper Junos
CVE-2023-44186Same product: Juniper Junos

Affected Assets

juniper
junos
19.4, 20.2, 20.3, 20.4, 21.1 · ≤ 19.4

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 1 hardening rule · 1 OS baseline
Validate
Prove the fix (OWASP ASVS)

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-755

Provides defined handling (alert and additional actions) for the exceptional condition of audit logging failure.

addresses: CWE-755

Supplies a concrete handling action (safe mode) for exceptional conditions, mitigating risks from improper or absent handling that could allow continued attacks.

addresses: CWE-755

By preparing users for contingency scenarios, the control promotes proper handling of exceptional conditions instead of default or unsafe behaviors.

addresses: CWE-755

An updated contingency plan defines current actions for exceptional conditions, reducing the window for attackers to exploit improper handling leading to system failure.

addresses: CWE-755

Procedures ensure proper handling of exceptional conditions to support effective incident response.

addresses: CWE-755

Incident response testing confirms proper handling of exceptional conditions to limit exploit impact.

addresses: CWE-755

Gives users guidance on incident handling, reducing improper handling of exceptional conditions that could stem from exploited weaknesses.

addresses: CWE-755

Enforces structured response to exceptional conditions so the system cannot remain in an unsafe state.

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 explicitly require proper exception and error handling during design and coding.

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.

finds

Security testing in development and acceptance verifies correct handling of exceptional conditions.

degrades

Documented operating procedures may specify exception handling but do not guarantee implementation.

A.8.15 Logging partial match
finds

Logging captures unhandled exceptions, aiding detection but not preventing the weakness.

finds

Monitoring can surface unhandled exceptions but does not enforce proper handling.

prevents

Secure SDLC mandates exception-handling requirements and testing that directly prevent improper handling of exceptional conditions.

prevents

Application security requirements explicitly include handling of error and exceptional conditions.

References