Format string flaw in Junos OS on SRX lets remote attackers run code
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-134 and the CVSS impact.
Summary
Juniper Networks Junos OS on SRX Series is affected across several release lines, each before its fixed version. An externally controlled format string (CWE-134) in the ipfd daemon lets the software process attacker input as a format string. An unauthenticated network attacker who compromises or impersonates a configured HTTPS feed server can execute code with root privileges.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
An Use of Externally-Controlled Format String vulnerability in the ipfd daemon of Juniper Networks Junos OS on SRX Series allows an unauthenticated network-based attacker to execute code with root privileges via a compromised or impersonated configured HTTPS feed server.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
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-S5; 25.2 to before 25.2R2-S2; 25.4 to before 25.4R1-S3; 26.2 to before 26.2R1-S2 | 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3, 26.2R1-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-S5; 25.2 to before 25.2R2-S2; 25.4 to before 25.4R1-S3; 26.2 to before 26.2R1-S2 Fixed in 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3, 26.2R1-S2 Patch available CNA
Remediation
Upgrade Junos OS to 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3 or 26.2R1-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-S5, 25.2R2-S2, 25.4R1-S3, 26.2R1-S2
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Advisory ·
Juniper Networks Junos OS — supportportal.juniper.net/JSA112186
11 records Highest priority Priority MEDIUM 8 MEDIUM, 3 LOW
Other records, highest priority first
- TI-2026-74316 Stack buffer overflow in Junos OS SRX Series lets attackers run codePriority MEDIUM 49
- TI-2026-74191 Heap buffer overflow in Junos OS SRX Series via malformed IPv4 packetsPriority MEDIUM 48
- TI-2026-74251 XML injection in Junos OS SRX Series allows arbitrary config commitsPriority MEDIUM 42
Timeline
- 2026-10-15 Threatist record created from CVE-2026-102062
- 2026-10-15 CISA SSVC decision points changed
- 2026-10-16 Priority changed: LOW → MEDIUM
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