Security Resilience

CVE-2023-44203

Juniper Junos ≤ 20.4

Published
13 October 2023
Modified
21 November 2024
Patch / advisory
CVSS Score v3.1 6.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0030 21th percentile
Risk Priority 49 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-44203 is a medium-severity Improper Check or Handling of Exceptional Conditions (CWE-703) vulnerability in Juniper Junos. Its CVSS base score is 6.5 (Medium).

Operationally, ranked at the 21th 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

An Improper Check or Handling of Exceptional Conditions vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS on QFX5000 Series, EX2300, EX3400, EX4100, EX4400 and EX4600 allows a adjacent attacker to send specific traffic, which leads to…

more

packet flooding, resulting in a Denial of Service (DoS). When a specific IGMP packet is received in an isolated VLAN, it is duplicated to all other ports under the primary VLAN, which causes a flood. This issue affects QFX5000 series, EX2300, EX3400, EX4100, EX4400 and EX4600 platforms only. This issue affects Juniper Junos OS on on QFX5000 Series, EX2300, EX3400, EX4100, EX4400 and EX4600: * All versions prior to 20.4R3-S5; * 21.1 versions prior to 21.1R3-S4; * 21.2 versions prior to 21.2R3-S3; * 21.3 versions prior to 21.3R3-S5; * 21.4 versions prior to 21.4R3-S2; * 22.1 versions prior to 22.1R3; * 22.2 versions prior to 22.2R3; * 22.3 versions prior to 22.3R2.

CWE(s)

Related Threats

CVEs Like This One

CVE-2024-21595Same product: Juniper Ex4100
CVE-2024-39514Same product: Juniper Junos
CVE-2023-28959Same product: Juniper Junos
CVE-2023-36849Same product: Juniper Junos
CVE-2024-21593Same product: Juniper Junos
CVE-2023-22413Same product: Juniper Junos
CVE-2023-36831Same product: Juniper Junos
CVE-2023-22405Same product: Juniper Ex4600
CVE-2025-30644Same product: Juniper Ex2300
CVE-2026-33773Same product: Juniper Ex2300

Affected Assets

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

Mitigating Controls

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-703

Implements explicit check and handling for the exceptional condition of audit logging process failure.

addresses: CWE-703

Establishing and monitoring system metrics with correlation and response actions helps identify and address improper handling of exceptional conditions.

addresses: CWE-703

Provides a defined response to detected conditions by restricting operation, ensuring exceptional conditions are handled rather than ignored or mishandled.

addresses: CWE-703

Contingency training equips users with defined procedures to check and respond to exceptional conditions during disruptions, reducing exploitation of mishandled errors.

addresses: CWE-703

Testing verifies the system's ability to detect, handle, and recover from exceptional conditions as part of the plan, reducing exploitability of improper exception handling.

addresses: CWE-703

Regular updates keep contingency procedures aligned with system changes, providing structured handling for exceptional conditions that would otherwise allow unmitigated exploitation.

addresses: CWE-703

Policy defines checks and handling for exceptional conditions arising from security incidents.

addresses: CWE-703

Performing IR tests ensures exceptional conditions are properly checked and handled to enable effective response.

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.

removes

A.8.26 only requires that security requirements (including resilience against attacks like SQL injection) be identified and specified during development or acquisition; it does not itself remove, fix, or eliminate any exceptional-condition handling defects already present in code.

removes

A.8.28 mandates secure coding practices, principles, defect removal during coding/review, and prohibiting insecure techniques that directly produce improper exception handling; this removes most instances of the first-party code defect, with a bounded remainder in incomplete adoption or edge-case defects not captured by the baseline.

Hardening callouts derived

DISA STIG baselines are authored against specific weaknesses. Where this CVE cites a broad weakness class, the mapping is not asserted at that abstraction (owner ruling, 2026-09-25: grade only at Base and below), so no rule is shown here rather than a rule shown against the wrong grain.

  • No fine-grained STIG row for CWE-703, a pillar-level weakness, and none of its children carries one either.

References