CVE-2025-59960
Juniper Junos ≤ 21.2
Raw vector
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:L/SI:N/SA:H/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:Y/R:U/V:C/RE:M/U:AmberSummary
CVE-2025-59960 is a medium-severity Improper Check for Unusual or Exceptional Conditions (CWE-754) vulnerability in Juniper Junos. Its CVSS base score is 6.3 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Service Stop (T1489); ranked at the 15th 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 SI-10 (Information Input Validation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2025-59960 is an Improper Check for Unusual or Exceptional Conditions vulnerability (CWE-754) in the Juniper DHCP service (jdhcpd) of Juniper Networks Junos OS and Junos OS Evolved. The flaw affects numerous versions, including all Junos OS releases prior to 21.2R3-S10, versions from 21.4 prior to 21.4R3-S12, all 22.2 versions, and ranges in later branches up to 25.2R2 such as 22.4 prior to 22.4R3-S8, 23.2 prior to 23.2R2-S5, and others; similar version ranges apply to Junos OS Evolved. By default, the DHCP relay agent inserts its own Option 82 information when forwarding client requests, but in 'forward-only' mode, it fails to drop specific DHCP DISCOVER packets containing Option 82 unless 'trust-option82' is configured, instead forwarding them unmodified to the DHCP server.
An attacker with adjacent network access (AV:A) and no privileges (PR:N) can exploit this by sending crafted DHCP DISCOVER packets with Option 82 from one subnet. The relay agent forwards these unmodified to the downstream DHCP server, causing it to allocate addresses from unintended pools and exhaust those of other subnets. This results in a high-impact Denial of Service (DoS) on the DHCP server (A:H, scope changed S:C), with a CVSS v3.1 base score of 7.4.
The Juniper security advisory at https://kb.juniper.net/JSA103149 details fixed versions for mitigation, recommending upgrades to patched releases such as Junos OS 21.2R3-S10 or later in the respective branches, and equivalent Junos OS Evolved versions like 21.4R3-S12-EVO. Additional guidance is available via https://supportportal.juniper.net/.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-2718
Vulnerability Data
An Improper Check for Unusual or Exceptional Conditions vulnerability in the Juniper DHCP service (jdhcpd) of Juniper Networks Junos OS and Junos OS Evolved allows a DHCP client in one subnet to exhaust the address pools of other subnets, leading…
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to a Denial of Service (DoS) on the downstream DHCP server. By default, the DHCP relay agent inserts its own Option 82 information when forwarding client requests, optionally replacing any Option 82 information provided by the client. When a specific DHCP DISCOVER is received in 'forward-only' mode with Option 82, the device should drop the message unless 'trust-option82' is configured. Instead, the DHCP relay forwards these packets to the DHCP server unmodified, which uses up addresses in the DHCP server's address pool, ultimately leading to address pool exhaustion. This issue affects Junos OS: * all versions before 21.2R3-S10, * from 21.4 before 21.4R3-S12, * all versions of 22.2, * from 22.4 before 22.4R3-S8, * from 23.2 before 23.2R2-S5, * from 23.4 before 23.4R2-S6, * from 24.2 before 24.2R2-S2, * from 24.4 before 24.4R2, * from 25.2 before 25.2R1-S1, 25.2R2. Junos OS Evolved: * all versions before 21.4R3-S12-EVO, * all versions of 22.2-EVO, * from 22.4 before 22.4R3-S8-EVO, * from 23.2 before 23.2R2-S5-EVO, * from 23.4 before 23.4R2-S6-EVO, * from 24.2 before 24.2R2-S2-EVO, * from 24.4 before 24.4R2-EVO, * from 25.2 before 25.2R1-S1-EVO, 25.2R2-EVO.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 7 hardening rules · 2 OS baselines
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Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation explicitly exercises unusual conditions to find missing or incorrect checks.
Input validation directly requires checking for unexpected or malformed conditions before they propagate.
Security engineering principles include structured handling of edge cases and exceptions during design.
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 development practices directly require proper checks and handling for exceptional conditions throughout the SDLC.
Runtime monitoring of software and environments can detect adverse events triggered by unhandled exceptional conditions.
Generating logs of exceptions and errors enables detection of improper handling of unusual conditions.
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.
Security testing in development and acceptance verifies handling of error and exceptional conditions.
Logging can record unhandled exceptions but does not prevent the weakness itself.
Monitoring may detect symptoms of unhandled conditions but does not eliminate the root weakness.
Secure development life cycle mandates exception handling and input validation that directly prevent missing checks for unusual conditions.
Application security requirements explicitly call for handling of exceptional conditions and error paths.
Secure system architecture and engineering principles require robust error and exception handling mechanisms.
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 (2 rules)
- V-248574 YUM must be configured to prevent the installation of patches, service packs, device drivers, or OL 8 system components that have not been digitally signed using a certificate that is recognized and approved by the organization. prevents CWE-754
- V-248575 OL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. prevents CWE-754
Oracle Linux 9 (1 rule)
- V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-754