Cyber Resilience

CVE-2024-39528

Memory Safety in Juniper Junos ≤ 21.2

Published
11 July 2024
Modified
21 November 2024
Patch / advisory
CVSS Score v4 6.0
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0034 26th percentile
Risk Priority 34 floored blend · peak EPSS

Summary

CVE-2024-39528 is a medium-severity Use After Free (CWE-416) vulnerability in Juniper Junos. Its CVSS base score is 6.0 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Client Execution (T1203); ranked at the 26th 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 SA-11 (Developer Testing and Evaluation) and SA-8 (Security and Privacy Engineering Principles) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

A Use After Free vulnerability in the Routing Protocol Daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an authenticated, network-based attacker to cause a Denial of Service (DoS).On all Junos OS and Junos Evolved platforms, if…

more

a routing-instance deactivation is triggered, and at the same time a specific SNMP request is received, a segmentation fault occurs which causes rpd to crash and restart. This issue affects: Junos OS: * All versions before 21.2R3-S8, * 21.4 versions before 21.4R3-S5, * 22.2 versions before 22.2R3-S3, * 22.3 versions before 22.3R3-S2, * 22.4 versions before 22.4R3, * 23.2 versions before 23.2R2. Junos OS Evolved: * All versions before 21.2R3-S8-EVO, * 21.4-EVO versions before 21.4R3-S5-EVO, * 22.2-EVO versions before 22.2R3-S3-EVO, * 22.3-EVO versions before 22.3R3-S2-EVO, * 22.4-EVO versions before 22.4R3-EVO, * 23.2-EVO versions before 23.2R2-EVO.

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.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-21908Same product: Juniper Junos
CVE-2026-21921Same product: Juniper Junos
CVE-2024-30386Same product: Juniper Junos
CVE-2023-28980Same product: Juniper Junos
CVE-2025-52946Same product: Juniper Junos
CVE-2023-22402Same product: Juniper Junos Os Evolved
CVE-2023-36833Same product: Juniper Junos Os Evolved
CVE-2024-30378Same product: Juniper Junos
CVE-2023-28984Same product: Juniper Junos
CVE-2025-26681Shared CWE-416

Affected Assets

juniper
junos
21.2, 21.4, 22.2, 22.3, 22.4 · ≤ 21.2
juniper
junos os evolved
21.2, 21.4, 22.2, 22.4, 23.2 · ≤ 21.2

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 3 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V1.4.3

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation can discover use-after-free bugs through dynamic analysis or fuzzing.

Engineering principles can require memory-safe constructs or languages that structurally avoid introducing use-after-free.

Process isolation confines the blast radius of use-after-free memory corruption to a single execution domain.

Memory protection controls limit exploitation impact by blocking unauthorized code execution from dangling pointers.

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 incorporate memory-safety tooling and reviews that prevent most use-after-free defects.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover use-after-free issues via scanning or analysis but do not prevent their introduction.

PR.PS-02 partial match
prevents

Routine patching removes known use-after-free instances after they have been introduced in released software.

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 can detect use-after-free bugs before release.

prevents

Secure SDLC mandates memory-safety practices that reduce use-after-free defects.

prevents

Application security requirements can specify memory-management rules that mitigate use-after-free.

prevents

Secure architecture principles include memory-safety design choices that limit use-after-free exposure.

prevents

Secure coding standards directly prescribe avoidance of use-after-free patterns.

prevents

Change-management processes help ensure memory-safety fixes are deployed consistently.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248592 OL 8 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416
RHEL 8 (1 rule)
  • V-230279 RHEL 8 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416
RHEL 9 (1 rule)
  • V-257794 RHEL 9 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416

References