Quick answers
- Is CVE-2026-101990 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-101990 being exploited in the wild.
- How severe is CVE-2026-101990?
- Critical severity, with a CVSS score of 9.8, published 14 October 2026.
- Which products and versions are affected?
- Juniper Networks Junos OS; Juniper Networks Junos OS Evolved.
- Is there a fix for CVE-2026-101990?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-101990 attacked?
- It is attacked over the network, in an operating system.
- Am I affected by CVE-2026-101990?
- Check whether you run Juniper Networks Junos OS or Juniper Networks Junos OS Evolved. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A stack-based buffer overflow exists in the routing protocol daemon (rpd) when processing flow-spec updates selected for re-advertisement. An attacker acting as a configured BGP peer can trigger the overflow via a malformed flow-spec message, causing denial of service on Junos OS Evolved or remote code execution on Junos OS. The vulnerability requires the attacker to be an established BGP peer.
Affected products
- Juniper Networks Junos OS
- Juniper Networks Junos OS Evolved
Timeline
- 2026-10-14: disclosed