Junos OS and Junos OS Evolved: A BGP-LS peer causes heap data disclosure when traffic-engineering routing is enabled

published 2026-10-14 25 d ago modified 2026-10-15 24 d ago also EUVD-2026-101451

cvss: 3.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 8%
public exploits: 0; none known

An Improper Handling of Length Parameter Inconsistency vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows a configured BGP-LS peer to cause heap data disclosure via a malformed UPDATE sent over a session with the traffic-engineering address family enabled.

Patch / fix

fixed in 2

Juniper Networks Junos OS 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3, 26.2R1-S2
Juniper Networks Junos OS Evolved 23.2R2-S7.7-EVO, 23.4R2-S8.11-EVO, 24.2R2-S5.6-EVO, 24.4R2-S5-EVO, 25.2R2-S2-EVO, 25.2X100-D35-EVO, 25.4R1-S3-EVO, 25.4X300-D40-EVO, 26.2R1-S2-EVO

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 25 d ago (2026-10-14)

Exploit prediction

0.19% chance of exploitation in the next 30 days, higher than 8% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	3.1	CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
CNA	4.0	5.3	CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
CNA	4.0	5.3	CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/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:X/R:X/V:X/RE:X/U:X

Affected products

Juniper Networks Junos OS
Juniper Networks Junos OS Evolved

Classification

Weakness

CWE-130 Improper Handling of Length Parameter Inconsistency

References

supportportal.juniper.net /JSA112187
vendor-advisory

Sources

CVE List CVE-2026-101991
NVD CVE-2026-101991

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary