CVE-2023-36843 | Junos OS: SRX Series: The PFE will crash on receiving malformed SSL traffic when Sky ATP is enabled

An Improper Handling of Inconsistent Special Elements vulnerability in the Junos Services Framework (jsf) module of Juniper Networks Junos OS allows an unauthenticated network based attacker to cause a crash in the Packet Forwarding Engine (pfe) and thereby resulting in a Denial of Service (DoS). Upon receiving malformed SSL traffic, the PFE crashes. A manual restart will be needed to recover the device. This issue only affects devices with Juniper Networks Advanced Threat Prevention (ATP) Cloud enabled with Encrypted Traffic Insights (configured via ‘security-metadata-streaming policy’). This issue affects Juniper Networks Junos OS: * All versions prior to 20.4R3-S8, 20.4R3-S9; * 21.1 version 21.1R1 and later versions; * 21.2 versions prior to 21.2R3-S6; * 21.3 versions prior to 21.3R3-S5; * 21.4 versions prior to 21.4R3-S5; * 22.1 versions prior to 22.1R3-S4; * 22.2 versions prior to 22.2R3-S2; * 22.3 versions prior to 22.3R2-S2, 22.3R3; * 22.4 versions prior to 22.4R2-S1, 22.4R3;

Published: 2023-10-12 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-36843 is rated Moderate Risk (44.9/100): CVSS High severity, with low exploitation likelihood (EPSS 0.55%). 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-2023-36843

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 2026-06-15 0.09% 0.55% +0.46%
2 2025-11-21 0.20% 0.09% -0.11%
3 2025-11-18 0.20%

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-36843

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
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]
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-2023-36843

Affected software / configurations for CVE-2023-36843

Vendor Product Version Raw CPE
juniper junos < 20.4 cpe:2.3:o:juniper:junos:*:*:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:-:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:r1:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:r1-s1:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:r2:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:r2-s1:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:r2-s2:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:r3:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:r3-s1:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:r3-s2:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:r3-s3:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:r3-s4:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:r3-s5:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:r3-s6:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:r3-s7:*:*:*:*:*:*
juniper junos 20.4 cpe:2.3:o:juniper:junos:20.4:r3-s9:*:*:*:*:*:*
juniper junos 21.1 cpe:2.3:o:juniper:junos:21.1:r1:*:*:*:*:*:*
juniper junos 21.1 cpe:2.3:o:juniper:junos:21.1:r1-s1:*:*:*:*:*:*
juniper junos 21.1 cpe:2.3:o:juniper:junos:21.1:r2:*:*:*:*:*:*
juniper junos 21.1 cpe:2.3:o:juniper:junos:21.1:r2-s1:*:*:*:*:*:*
juniper junos 21.1 cpe:2.3:o:juniper:junos:21.1:r2-s2:*:*:*:*:*:*
juniper junos 21.1 cpe:2.3:o:juniper:junos:21.1:r3:*:*:*:*:*:*
juniper junos 21.1 cpe:2.3:o:juniper:junos:21.1:r3-s1:*:*:*:*:*:*
juniper junos 21.1 cpe:2.3:o:juniper:junos:21.1:r3-s2:*:*:*:*:*:*
juniper junos 21.1 cpe:2.3:o:juniper:junos:21.1:r3-s3:*:*:*:*:*:*
juniper junos 21.1 cpe:2.3:o:juniper:junos:21.1:r3-s4:*:*:*:*:*:*
juniper junos 21.1 cpe:2.3:o:juniper:junos:21.1:r3-s5:*:*:*:*:*:*
juniper junos 21.2 cpe:2.3:o:juniper:junos:21.2:-:*:*:*:*:*:*
juniper junos 21.2 cpe:2.3:o:juniper:junos:21.2:r1:*:*:*:*:*:*
juniper junos 21.2 cpe:2.3:o:juniper:junos:21.2:r1-s1:*:*:*:*:*:*
juniper junos 21.2 cpe:2.3:o:juniper:junos:21.2:r1-s2:*:*:*:*:*:*
juniper junos 21.2 cpe:2.3:o:juniper:junos:21.2:r2:*:*:*:*:*:*
juniper junos 21.2 cpe:2.3:o:juniper:junos:21.2:r2-s1:*:*:*:*:*:*
juniper junos 21.2 cpe:2.3:o:juniper:junos:21.2:r2-s2:*:*:*:*:*:*
juniper junos 21.2 cpe:2.3:o:juniper:junos:21.2:r3:*:*:*:*:*:*
juniper junos 21.2 cpe:2.3:o:juniper:junos:21.2:r3-s1:*:*:*:*:*:*
juniper junos 21.2 cpe:2.3:o:juniper:junos:21.2:r3-s2:*:*:*:*:*:*
juniper junos 21.2 cpe:2.3:o:juniper:junos:21.2:r3-s3:*:*:*:*:*:*
juniper junos 21.2 cpe:2.3:o:juniper:junos:21.2:r3-s4:*:*:*:*:*:*
juniper junos 21.2 cpe:2.3:o:juniper:junos:21.2:r3-s5:*:*:*:*:*:*
juniper junos 21.3 cpe:2.3:o:juniper:junos:21.3:-:*:*:*:*:*:*
juniper junos 21.3 cpe:2.3:o:juniper:junos:21.3:r1:*:*:*:*:*:*
juniper junos 21.3 cpe:2.3:o:juniper:junos:21.3:r1-s1:*:*:*:*:*:*
juniper junos 21.3 cpe:2.3:o:juniper:junos:21.3:r1-s2:*:*:*:*:*:*
juniper junos 21.3 cpe:2.3:o:juniper:junos:21.3:r2:*:*:*:*:*:*
juniper junos 21.3 cpe:2.3:o:juniper:junos:21.3:r2-s1:*:*:*:*:*:*
juniper junos 21.3 cpe:2.3:o:juniper:junos:21.3:r2-s2:*:*:*:*:*:*
juniper junos 21.3 cpe:2.3:o:juniper:junos:21.3:r3:*:*:*:*:*:*
juniper junos 21.3 cpe:2.3:o:juniper:junos:21.3:r3-s1:*:*:*:*:*:*
juniper junos 21.3 cpe:2.3:o:juniper:junos:21.3:r3-s2:*:*:*:*:*:*
juniper junos 21.3 cpe:2.3:o:juniper:junos:21.3:r3-s3:*:*:*:*:*:*
juniper junos 21.3 cpe:2.3:o:juniper:junos:21.3:r3-s4:*:*:*:*:*:*
juniper junos 21.4 cpe:2.3:o:juniper:junos:21.4:-:*:*:*:*:*:*
juniper junos 21.4 cpe:2.3:o:juniper:junos:21.4:r1:*:*:*:*:*:*
juniper junos 21.4 cpe:2.3:o:juniper:junos:21.4:r1-s1:*:*:*:*:*:*
juniper junos 21.4 cpe:2.3:o:juniper:junos:21.4:r1-s2:*:*:*:*:*:*
juniper junos 21.4 cpe:2.3:o:juniper:junos:21.4:r2:*:*:*:*:*:*
juniper junos 21.4 cpe:2.3:o:juniper:junos:21.4:r2-s1:*:*:*:*:*:*
juniper junos 21.4 cpe:2.3:o:juniper:junos:21.4:r2-s2:*:*:*:*:*:*
juniper junos 21.4 cpe:2.3:o:juniper:junos:21.4:r3:*:*:*:*:*:*
juniper junos 21.4 cpe:2.3:o:juniper:junos:21.4:r3-s1:*:*:*:*:*:*
juniper junos 21.4 cpe:2.3:o:juniper:junos:21.4:r3-s2:*:*:*:*:*:*
juniper junos 21.4 cpe:2.3:o:juniper:junos:21.4:r3-s3:*:*:*:*:*:*
juniper junos 21.4 cpe:2.3:o:juniper:junos:21.4:r3-s4:*:*:*:*:*:*
juniper junos 22.1 cpe:2.3:o:juniper:junos:22.1:r1:*:*:*:*:*:*
juniper junos 22.1 cpe:2.3:o:juniper:junos:22.1:r1-s1:*:*:*:*:*:*
juniper junos 22.1 cpe:2.3:o:juniper:junos:22.1:r1-s2:*:*:*:*:*:*
juniper junos 22.1 cpe:2.3:o:juniper:junos:22.1:r2:*:*:*:*:*:*
juniper junos 22.1 cpe:2.3:o:juniper:junos:22.1:r2-s1:*:*:*:*:*:*
juniper junos 22.1 cpe:2.3:o:juniper:junos:22.1:r2-s2:*:*:*:*:*:*
juniper junos 22.1 cpe:2.3:o:juniper:junos:22.1:r3:*:*:*:*:*:*
juniper junos 22.1 cpe:2.3:o:juniper:junos:22.1:r3-s1:*:*:*:*:*:*
juniper junos 22.2 cpe:2.3:o:juniper:junos:22.2:r1:*:*:*:*:*:*
juniper junos 22.2 cpe:2.3:o:juniper:junos:22.2:r1-s1:*:*:*:*:*:*
juniper junos 22.2 cpe:2.3:o:juniper:junos:22.2:r1-s2:*:*:*:*:*:*
juniper junos 22.2 cpe:2.3:o:juniper:junos:22.2:r2:*:*:*:*:*:*
juniper junos 22.2 cpe:2.3:o:juniper:junos:22.2:r2-s1:*:*:*:*:*:*
juniper junos 22.2 cpe:2.3:o:juniper:junos:22.2:r2-s2:*:*:*:*:*:*
juniper junos 22.2 cpe:2.3:o:juniper:junos:22.2:r3:*:*:*:*:*:*
juniper junos 22.2 cpe:2.3:o:juniper:junos:22.2:r3-s1:*:*:*:*:*:*

References for CVE-2023-36843

cvelogic Threat Intelligence