CVE-2026-33797
published 2026-04-09CVE-2026-33797: An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a specific…
PriorityP340high7.4CVSS 3.1
AVAACLPRNUINSCCNINAH
EPSS
0.17%
6.2th percentile
An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a specific genuine BGP packet in an already established BGP session to reset only that session causing a Denial of Service (DoS). An attacker repeatedly sending the packet will sustain the Denial of Service (DoS).This issue affects Junos OS: * 25.2 versions before 25.2R2 This issue does not affect Junos OS versions before 25.2R1. This issue affects Junos OS Evolved: * 25.2-EVO versions before 25.2R2-EVO This issue does not affect Junos OS Evolved versions before 25.2R1-EVO. eBGP and iBGP are affected. IPv4 and IPv6 are affected.
Affected
5 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| juniper | junos | — | — |
| juniper | junos_os | — | — |
| juniper | junos_os_evolved | — | — |
| juniper_networks | junos_os | >= 25.2 < 25.2R2 | 25.2R2 |
| juniper_networks | junos_os_evolved | >= 25.2 < 25.2R2-EVO | 25.2R2-EVO |
CVSS provenance
nvdv3.17.4HIGHCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
nvdv4.07.1HIGHCVSS: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
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GHSA
GHSA-3rpc-j6fw-646r: An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a s
ghsa_unreviewed·2026-04-10
CVE-2026-33797 [HIGH] CWE-20 GHSA-3rpc-j6fw-646r: An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a s
An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a specific genuine BGP packet in an already established BGP session to reset only that session causing a Denial of Service (DoS).
An attacker repeatedly sending the packet will sustain the Denial of Service (DoS).This issue affects Junos OS:
* 25.2 versions before 25.2R2
This issue doesn't not affected Junos OS versions before 25.2R1.
This issue affects Junos OS Evolved:
* 25.2-EVO versions before 25.2R2-EVO
This issue doesn't not affected Junos OS Evolved versions before 25.2R1-EVO.
eBGP and iBGP are affected.
IPv4 and IPv6 are affected.
VulDB
Juniper Junos OS/Junos OS Evolved up to 25.2R0/25.2R1 denial of service (JSA107850)
vuldb·2026-04-10·CVSS 7.1
CVE-2026-33797 [HIGH] Juniper Junos OS/Junos OS Evolved up to 25.2R0/25.2R1 denial of service (JSA107850)
A vulnerability, which was classified as problematic, was found in Juniper Junos OS and Junos OS Evolved up to 25.2R0/25.2R1. The affected element is an unknown function. The manipulation results in denial of service.
This vulnerability is identified as CVE-2026-33797. The attack can only be performed from the local network. There is not any exploit available.
You should upgrade the affected component.
Juniper
CVE-2026-33797: An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a s
vendor_juniper·2026-04-09·CVSS 7.4
CVE-2026-33797 [HIGH] CWE-20 CVE-2026-33797: An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a s
CVE-2026-33797: An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a specific genuine BGP packet in an already established BGP session to reset only that session causing a Denial of Service (DoS).
An attacker repeatedly sending the packet will sustain the Denial of Service (DoS).This issue affects Junos OS:
* 25.2 versions before 25.2R2
This issue doesn't not affected Junos OS versions before 25.2R1.
This issue affects Junos OS Evolved:
* 25.2-EVO versions before 25.2R2-EVO
This issue doesn't not affected Junos OS Evolved versions before 25.2R1-EVO.
eBGP and iBGP are affected.
IPv4 and IPv6 are affected.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-04-09
Published