CVE-2026-101991

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

State: Published
Severity: 5.3 Medium
Published: Oct 14, 2026
Updated: Oct 14, 2026
Reserved: Sep 28, 2026

Description

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.

Scores

CVSS	Score	Vector	Source
4.0	5.3 Medium	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	juniper
3.1	3.1 Low	CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N	juniper

Weaknesses

CWE-130 Improper Handling of Length Parameter Inconsistency

Affected Products

Product	Versions
Junos OSJuniper Networks	before 23.2R2-S7.7Affected 23.4 to before 23.4R2-S8.13Affected 24.2 to before 24.2R2-S5.5Affected 24.4 to before 24.4R2-S5Affected 25.2 to before 25.2R2-S2Affected 25.4 to before 25.4R1-S3Affected 26.2 to before 26.2R1-S2Affected
Junos OS EvolvedJuniper Networks	before 23.2R2-S7.7-EVOAffected 23.4 to before 23.4R2-S8.11-EVOAffected 24.2 to before 24.2R2-S5.6-EVOAffected 24.4 to before 24.4R2-S5-EVOAffected 25.2 to before 25.2R2-S2-EVOAffected 25.4 to before 25.4R1-S3-EVOAffected 26.2 to before 26.2R1-S2-EVOAffected 23.4X100Affected 25.2X100 to before 25.2X100-D35-EVOAffected 25.4X300 to before 25.4X300-D40-EVOAffected

References

https://supportportal.juniper.net/JSA112187vendor-advisory

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