NULL pointer dereference in Junos OS on SRX Series causes DoS
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-476.
Summary
Juniper Networks Junos OS on SRX Series versions before 23.2R2-S7.7, from 23.4 before 23.4R2-S8.13, from 24.2 before 24.2R2-S5.5, from 24.4 before 24.4R2-S4, from 25.2 before 25.2R2-S1 and from 25.4 before 25.4R1-S2 are affected. A NULL pointer dereference (CWE-476) in the DNS plugin lets an unauthenticated network-based attacker crash the FPC and cause a complete denial of service when a single flow session carries multiple DNS queries, one matching a SecIntel feed and another sent for DGA analysis.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
A NULL Pointer Dereference vulnerability in the DNS plugin of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a complete Denial-of-Service (DoS). When multiple DNS queries are received in a single flow session, where one query matches a Security Intelligence (SecIntel) feed and another query is sent for DNS Domain Generation Algorithm (DGA) analysis, an error in processing logging of these asynchronous tasks can lead to an FPC crash. The exact timing conditions are outside an attacker's direct control. This issue affects Junos OS on SRX Series: * All versions before 23.2R2-S7.7; * from 23.4 before 23.4R2-S8.13; * from 24.2 before 24.2R2-S5.5; * from 24.4 before 24.4R2-S4; * from 25.2 before 25.2R2-S1; * from 25.4 before 25.4R1-S2.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Juniper | Junos OS | before 23.2R2-S7.7; 23.4 to before 23.4R2-S8.13; 24.2 to before 24.2R2-S5.5; 24.4 to before 24.4R2-S4; 25.2 to before 25.2R2-S1; 25.4 to before 25.4R1-S2 | 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S4, 25.2R2-S1, 25.4R1-S2 | Patch available | CNA |
- Junos OS VendorJuniper Affected before 23.2R2-S7.7; 23.4 to before 23.4R2-S8.13; 24.2 to before 24.2R2-S5.5; 24.4 to before 24.4R2-S4; 25.2 to before 25.2R2-S1; 25.4 to before 25.4R1-S2 Fixed in 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S4, 25.2R2-S1, 25.4R1-S2 Patch available CNA
Remediation
Upgrade to Junos OS 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S4, 25.2R2-S1 or 25.4R1-S2.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
- Fix · CNA Junos OS (Juniper Networks) Fixed in 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S4, 25.2R2-S1, 25.4R1-S2
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
Juniper Networks Junos OS 23.2R2-S7.7, 23.4R2-S8.13 and 4 more versions
2 records Highest priority Priority LOW 2 LOW
Other records, highest priority first
- TI-2026-74288 Junos OS on MX Series: malformed SyncE or PTP input causes RE switchoversPriority LOW 26
Timeline
- 2026-10-15 Threatist record created from CVE-2026-102086
References
More Juniper vulnerabilities
- TI-2023-18638 Junos OS: EX and SRX Series: A PHP vulnerability in J-Web allows an unauthenticated to… KEVCVSS 3.1CRITICAL 9.8
- TI-2020-01585 Out of Cycle Security Advisory: Junos OS: Security vulnerability in J-Web and web based (HTTP/HTTPS) services KEVCVSS 3.1CRITICAL 9.8
- TI-2015-06436 Juniper ScreenOS 6.2.0r15 through 6.2.0r18, 6.3.0r12 before 6.3.0r12b, 6.3.0r13 before… KEVCVSS 3.1CRITICAL 9.8
- TI-2022-20885 Apache Commons Text prior to 1.10.0 allows RCE when applied to untrusted input due to insecure interpolation defaults CVSS 3.1CRITICAL 9.8
- TI-2015-04610 Assertion failure in ISC BIND named via TKEY queries KEVCVSS 3.1HIGH 7.5
- TI-2025-15550 Junos OS: An local attacker with shell access can execute arbitrary code KEVCVSS 4.0MEDIUM 6.7
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences