CVE-2026-21909 is a memory leak vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved. An unauthenticated attacker on an adjacent IS-IS network can send specific update packets to exhaust memory, leading to a Denial of Service (DoS) condition by crashing rpd. This vulnerability has a CVSS score of 6.5 (Medium) due to its low attack complexity and unauthenticated nature, despite requiring adjacent network access. While there is no known active exploitation or public exploit code, the vulnerability has garnered significant community discussion, indicating awareness among security researchers.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
23.2CPE matchmatch criteria | cpe:2.3:o:juniper:junos:23.2:-:*:*:*:*:*:* | ||
23.2CPE matchmatch criteria | cpe:2.3:o:juniper:junos:23.2:r1:*:*:*:*:*:* | ||
23.2CPE matchmatch criteria | cpe:2.3:o:juniper:junos:23.2:r1-s1:*:*:*:*:*:* | ||
23.2CPE matchmatch criteria | cpe:2.3:o:juniper:junos:23.2:r1-s2:*:*:*:*:*:* | ||
23.4CPE matchmatch criteria | cpe:2.3:o:juniper:junos:23.4:-:*:*:*:*:*:* |
CVSS version used by this source: 4.0
CVSS:4.0/AV:A/AC:L/AT:N/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:C/RE:M/U:Green
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.0 Mastodon, and 0.1 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.