CVE-2025-52948
Juniper Junos ≤ 21.2
Raw vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/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:Y/R:A/V:X/RE:M/U:XSummary
CVE-2025-52948 is a high-severity Improper Handling of Exceptional Conditions (CWE-755) vulnerability in Juniper Junos. Its CVSS base score is 8.2 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Client Execution (T1203); ranked at the 36th 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 SC-24 (Fail in Known State) and SI-17 (Fail-safe Procedures) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-21153
Vulnerability Data
An Improper Handling of Exceptional Conditions vulnerability in Berkeley Packet Filter (BPF) processing of Juniper Networks Junos OS allows an attacker, in rare cases, sending specific, unknown traffic patterns to cause the FPC and system to crash and restart. BPF…
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provides a raw interface to data link layers in a protocol independent fashion. Internally within the Junos kernel, due to a rare timing issue (race condition), when a BPF instance is cloned, the newly created interface causes an internal structure leakage, leading to a system crash. The precise content and timing of the traffic patterns is indeterminate, but has been seen in a lab environment multiple times. This issue is more likely to occur when packet capturing is enabled. See required configuration below. This issue affects Junos OS: * all versions before 21.2R3-S9, * from 21.4 before 21.4R3-S10, * from 22.2 before 22.2R3-S6, * from 22.4 before 22.4R3-S7, * from 23.2 before 23.2R2-S3, * from 23.4 before 23.4R2-S3, * from 24.2 before 24.2R1-S1, 24.2R2.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 1 hardening rule · 1 OS baseline
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Mitigating Controls (NIST 800-53 r5) AI
Requires the system to fail to a known safe state on specified failures, limiting the impact of unhandled exceptional conditions.
Mandates explicit fail-safe procedures triggered by indicated failures, structurally preventing unhandled or mishandled exceptional conditions.
Requires generation of appropriate error messages on exceptional conditions, directly enforcing correct handling rather than silent or incorrect behavior.
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 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.
Security testing in development and acceptance verifies correct handling of exceptional conditions.
Documented operating procedures may specify exception handling but do not guarantee implementation.
Logging captures unhandled exceptions, aiding detection but not preventing the weakness.
Monitoring can surface unhandled exceptions but does not enforce proper handling.
Secure SDLC mandates exception-handling requirements and testing that directly prevent improper handling of exceptional conditions.
Application security requirements explicitly include handling of error and exceptional conditions.