CVE-2026-101983: Stack-Based Buffer Overflow Flaw in Juniper Networks Junos OS Scores 9.8 on CVSS
A newly published critical vulnerability in Juniper Networks Junos OS carries a CVSS score of 9.8. Here is what is affected and how to respond.
Key points
- CVE-2026-101983 affects Juniper Networks Junos OS.
- CVSS 9.8 (Critical).
- No exploitation confirmed yet.
A critical stack-based buffer overflow tracked as CVE-2026-101983 has been published in the National Vulnerability Database for Juniper Networks Junos OS, with a CVSS base score of 9.8.
At a glance
- CVE
- CVE-2026-101983
- Product
- Juniper Networks Junos OS
- CVSS
- 9.8 Critical
- Weakness
- stack-based buffer overflow
- Exploited
- No known exploitation
What is the vulnerability?
The NVD entry states: A Stack-based Buffer Overflow vulnerability in the httpd process of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated network attacker to cause remote code execution and denial of service via a J-Web virtual-domain configured.
Affected versions
| Vendor | Product | Versions |
|---|---|---|
| Juniper Networks | Junos OS | before 23.4R2-S8.13, before 24.2R2-S5.5, before 24.4R2-S5, before 25.2R2-S2 |
| Juniper Networks | Junos OS Evolved | before 23.4R2-S8.11-EVO, before 24.2R2-S5.6-EVO, before 24.4R2-S5-EVO, before 25.2R2-S2-EVO |
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Is it being exploited?
There is no public confirmation of exploitation at the time of publication. It does not appear in CISA's Known Exploited Vulnerabilities catalog. We will update this report if that changes.
What should you do?
- Identify whether the affected product and versions run in your environment.
- Apply the vendor update listed in the advisory as soon as it is available.
- Limit network exposure of the affected service until it is patched.
- Monitor the vendor advisory for updated guidance or exploitation reports.
What to do and how to stay safe: CVE-2026-101983
- Vulnerability severity scores ignore your specific architecture and context.
- Exploitability depends on network exposure and user behavior, not just code flaws.
- Prioritization requires continuous asset inventory and threat intelligence alignment.
Risk-based vulnerability management focuses your limited resources on the flaws that actually threaten your business. Start by mapping your critical assets and checking for active exploits to prioritize your backlog.
Step-by-step guide: Risk-Based Vulnerability Management: Prioritize Fixes by Actual Danger
General security guidance from the Threat Times newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
What is CVE-2026-101983?
CVE-2026-101983 is a stack-based buffer overflow vulnerability in Juniper Networks Junos OS.
How severe is CVE-2026-101983?
It has a CVSS score of 9.8 Critical.
Is CVE-2026-101983 being exploited?
There is no public confirmation of exploitation at the time of publication.
