CVE-2025-21598 | Junos OS and Junos OS Evolved: When BGP traceoptions are configured, receipt of malformed BGP packets causes RPD to crash

An Out-of-bounds Read vulnerability in Juniper Networks Junos OS and Junos OS Evolved's routing protocol daemon (rpd) allows an unauthenticated, network-based attacker to send malformed BGP packets to a device configured with packet receive trace options enabled to crash rpd. This issue affects: Junos OS:  * from 21.2R3-S8 before 21.2R3-S9,  * from 21.4R3-S7 before 21.4R3-S9,  * from 22.2R3-S4 before 22.2R3-S5,  * from 22.3R3-S2 before 22.3R3-S4,  * from 22.4R3 before 22.4R3-S5,  * from 23.2R2 before 23.2R2-S2,  * from 23.4R1 before 23.4R2-S1,  * from 24.2R1 before 24.2R1-S1, 24.2R2. Junos OS Evolved: * from 21.4R3-S7-EVO before 21.4R3-S9-EVO,  * from 22.2R3-S4-EVO before 22.2R3-S5-EVO,  * from 22.3R3-S2-EVO before 22.3R3-S4-EVO,  * from 22.4R3-EVO before 22.4R3-S5-EVO,  * from 23.2R2-EVO before 23.2R2-S2-EVO,  * from 23.4R1-EVO before 23.4R2-S1-EVO,  * from 24.2R1-EVO before 24.2R1-S2-EVO, 24.2R2-EVO. This issue requires a BGP session to be established. This issue can propagate and multiply through multiple ASes until reaching vulnerable devices. This issue affects iBGP and eBGP. This issue affects IPv4 and IPv6. An indicator of compromise may be the presence of malformed update messages in a neighboring AS which is unaffected by this issue: For example, by issuing the command on the neighboring device:  show log messages Reviewing for similar messages from devices within proximity to each other may indicate this malformed packet is propagating:   rpd[<pid>]: Received malformed update from <IP address> (External AS <AS#>) and   rpd[<pid>]: Malformed Attribute

Published: 2025-01-09 Last update: 2026-01-26 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-21598 is rated Moderate Risk (58.7/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.74%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-21598

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-22 0.44% 0.74% +0.30%
2 2026-04-08 0.58% 0.44% -0.14%
3 2026-03-25 0.58%

Full EPSS history (16 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-21598

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.2 4.0 HIGH
CVSS:4.0/AV:N/AC:L/AT:P/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:Amber Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:P)
Additional preconditions must be present for exploitation.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:N)
No user interaction is required.
Vulnerable system confidentiality impact (VC:N)
No confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:N)
No integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:H)
High availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:L)
Limited availability impact on subsequent systems.
Exploit maturity (threat) (E:X)
Not defined: no reliable threat intelligence; scoring assumes the worst case (equivalent to Attacked).
Confidentiality requirement (CR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X)
Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X)
Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X)
Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X)
Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X)
Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X)
Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X)
Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X)
Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X)
Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X)
Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X)
Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X)
Not evaluated.
Automatable (supplemental) (AU:Y)
Yes: all four kill-chain steps (reconnaissance, weaponization, delivery, exploitation) can be automated.
Recovery (supplemental) (R:A)
Automatic: services recover on their own after an attack.
Value density (supplemental) (V:C)
Concentrated: a single exploit event controls rich resources (e.g., a central server).
Vulnerability response effort (supplemental) (RE:M)
Moderate effort (remote update, disable subsystem, simple upgrade with minor service impact).
Provider urgency (supplemental) (U:AMBER)
Amber: provider rates moderate urgency.
[email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]

Weakness enumeration for CVE-2025-21598

Affected software / configurations for CVE-2025-21598

Vendor Product Version Raw CPE
juniper junos 21.2 cpe:2.3:o:juniper:junos:21.2:r3-s8:*:*:*:*:*:*
juniper junos 21.4 cpe:2.3:o:juniper:junos:21.4:r3-s7:*:*:*:*:*:*
juniper junos 21.4 cpe:2.3:o:juniper:junos:21.4:r3-s8:*:*:*:*:*:*
juniper junos 22.2 cpe:2.3:o:juniper:junos:22.2:r3-s4:*:*:*:*:*:*
juniper junos 22.3 cpe:2.3:o:juniper:junos:22.3:r3-s2:*:*:*:*:*:*
juniper junos 22.3 cpe:2.3:o:juniper:junos:22.3:r3-s3:*:*:*:*:*:*
juniper junos 22.4 cpe:2.3:o:juniper:junos:22.4:r3:*:*:*:*:*:*
juniper junos 22.4 cpe:2.3:o:juniper:junos:22.4:r3-s1:*:*:*:*:*:*
juniper junos 22.4 cpe:2.3:o:juniper:junos:22.4:r3-s2:*:*:*:*:*:*
juniper junos 22.4 cpe:2.3:o:juniper:junos:22.4:r3-s3:*:*:*:*:*:*
juniper junos 22.4 cpe:2.3:o:juniper:junos:22.4:r3-s4:*:*:*:*:*:*
juniper junos 23.2 cpe:2.3:o:juniper:junos:23.2:r2:*:*:*:*:*:*
juniper junos 23.2 cpe:2.3:o:juniper:junos:23.2:r2-s1:*:*:*:*:*:*
juniper junos 23.4 cpe:2.3:o:juniper:junos:23.4:r1:*:*:*:*:*:*
juniper junos 23.4 cpe:2.3:o:juniper:junos:23.4:r1-s1:*:*:*:*:*:*
juniper junos 23.4 cpe:2.3:o:juniper:junos:23.4:r1-s2:*:*:*:*:*:*
juniper junos 23.4 cpe:2.3:o:juniper:junos:23.4:r2:*:*:*:*:*:*
juniper junos 24.2 cpe:2.3:o:juniper:junos:24.2:r1:*:*:*:*:*:*
juniper junos 24.2 cpe:2.3:o:juniper:junos:24.2:r2:*:*:*:*:*:*
juniper junos_os_evolved 21.4 cpe:2.3:o:juniper:junos_os_evolved:21.4:r3-s7:*:*:*:*:*:*
juniper junos_os_evolved 21.4 cpe:2.3:o:juniper:junos_os_evolved:21.4:r3-s8:*:*:*:*:*:*
juniper junos_os_evolved 22.2 cpe:2.3:o:juniper:junos_os_evolved:22.2:r3-s4:*:*:*:*:*:*
juniper junos_os_evolved 22.3 cpe:2.3:o:juniper:junos_os_evolved:22.3:r3-s2:*:*:*:*:*:*
juniper junos_os_evolved 22.3 cpe:2.3:o:juniper:junos_os_evolved:22.3:r3-s3:*:*:*:*:*:*
juniper junos_os_evolved 22.4 cpe:2.3:o:juniper:junos_os_evolved:22.4:r3:*:*:*:*:*:*
juniper junos_os_evolved 22.4 cpe:2.3:o:juniper:junos_os_evolved:22.4:r3-s1:*:*:*:*:*:*
juniper junos_os_evolved 22.4 cpe:2.3:o:juniper:junos_os_evolved:22.4:r3-s2:*:*:*:*:*:*
juniper junos_os_evolved 22.4 cpe:2.3:o:juniper:junos_os_evolved:22.4:r3-s3:*:*:*:*:*:*
juniper junos_os_evolved 22.4 cpe:2.3:o:juniper:junos_os_evolved:22.4:r3-s4:*:*:*:*:*:*
juniper junos_os_evolved 23.2 cpe:2.3:o:juniper:junos_os_evolved:23.2:r2:*:*:*:*:*:*
juniper junos_os_evolved 23.2 cpe:2.3:o:juniper:junos_os_evolved:23.2:r2-s1:*:*:*:*:*:*
juniper junos_os_evolved 23.4 cpe:2.3:o:juniper:junos_os_evolved:23.4:r1:*:*:*:*:*:*
juniper junos_os_evolved 23.4 cpe:2.3:o:juniper:junos_os_evolved:23.4:r1-s1:*:*:*:*:*:*
juniper junos_os_evolved 23.4 cpe:2.3:o:juniper:junos_os_evolved:23.4:r1-s2:*:*:*:*:*:*
juniper junos_os_evolved 23.4 cpe:2.3:o:juniper:junos_os_evolved:23.4:r2:*:*:*:*:*:*
juniper junos_os_evolved 24.2 cpe:2.3:o:juniper:junos_os_evolved:24.2:r1:*:*:*:*:*:*
juniper junos_os_evolved 24.2 cpe:2.3:o:juniper:junos_os_evolved:24.2:r2:*:*:*:*:*:*

References for CVE-2025-21598

cvelogic Threat Intelligence