CVE-2024-21595
Juniper Junos 21.4 … 23.1
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2024-21595 is a high-severity Improper Validation of Syntactic Correctness of Input (CWE-1286) vulnerability in Juniper Junos. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique LSASS Memory (T1003.001); ranked at the 44th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) — see the control section below for these in your framework.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2024-19243
Vulnerability Data
An Improper Validation of Syntactic Correctness of Input vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows a network-based, unauthenticated attacker to cause a Denial of Service (DoS). If an attacker sends high rate of specific…
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ICMP traffic to a device with VXLAN configured, this causes a deadlock of the PFE and results in the device becoming unresponsive. A manual restart will be required to recover the device. This issue only affects EX4100, EX4400, EX4600, QFX5000 Series devices. This issue affects: Juniper Networks Junos OS * 21.4R3 versions earlier than 21.4R3-S4; * 22.1R3 versions earlier than 22.1R3-S3; * 22.2R2 versions earlier than 22.2R3-S1; * 22.3 versions earlier than 22.3R2-S2, 22.3R3; * 22.4 versions earlier than 22.4R2; * 23.1 versions earlier than 23.1R2.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V1.4.2V2.2.2V3.5.5V5.4.1
Mitigating Controls (NIST 800-53 r5) AI
SI-10 requires validation of information inputs for correctness, directly stopping syntactic validation failures from being introduced or exploitable.
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.
Secure SDLC practices directly require syntactic input validation to prevent malformed data 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.
A.8.25 mandates secure SDLC practices including secure coding guidelines, security requirements, checkpoints, testing (scans/penetration), and developer training that reach syntactic validation defects, but leaves a bounded remainder (e.g. incomplete enforcement across all parsers, second-order inputs, or outsourced components where assurance is only obtained not enforced).
Application security requirements explicitly call for validation of input syntax.
A.8.27 mandates security engineering principles including data validation/sanitization, distrust external input, security by design, and design reviews against attack patterns, which directly stops syntactic validation flaws from reaching production in most cases; the bounded remainder is incomplete application to outsourced development, legacy code, or post-design changes.
Secure coding standards directly require proper syntactic validation of all inputs.
Security testing in development catches missing or incorrect syntax validation.