CVE-2025-52948
Junos OS: Specific unknown traffic pattern causes FPC and system to crash when packet capturing is enabled
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 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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
8.2
Junos OS: Specific unknown traffic pattern causes FPC and system to crash when packet capturing is enabled
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 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.
- Record
CVE-2025-52948- CVSS 4.0
- 8.2 High
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/AU:Y/R:A/RE:M - CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-755
- Updated
- 2026-11-02
EUVDEUVD-2025-21153
8.2
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 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.
- Record
EUVD-2025-21153- CVSS 4.0
- 8.2 High
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/AU:Y/R:A/RE:M - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-996g-m3p2-jr77
8.2
An Improper Handling of Exceptional Conditions vulnerability in Berkeley Packet Filter (BPF)...
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 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.
- Record
GHSA-996g-m3p2-jr77- CVSS 4.0
- 8.2 High
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:X - CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-755
- Updated
- 2026-11-02
NVD
8.2
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 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.
- Record
CVE-2025-52948- CVSS 4.0
- 8.2 High
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:X - CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-755
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2025-52948 is a high vulnerability (CVSS 8.2) in Juniper Junos, published July 11, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.50%, the 42nd percentile. No source names a fixed version.