CVE-2021-0242— Junos OS: EX4300: FPC crash upon receipt of specific frames on an interface without L2PT or dot1x configured
Quick assessment
Affected
Juniper Networks Junos OS
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Juniper Networks Junos OS是美国瞻博网络（Juniper Networks）公司的一套专用于该公司的硬件设备的网络操作系统。该操作系统提供了安全编程接口和Junos SDK。 Junos OS 存在缓冲区错误漏洞，该漏洞允许远程攻击者执行拒绝服务(DoS)攻击。
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I. Basic Information for CVE-2021-0242
Vulnerability Information
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Vulnerability Title
Junos OS: EX4300: FPC crash upon receipt of specific frames on an interface without L2PT or dot1x configured
Source: CVE Program / CVE List V5
Vulnerability Description
A vulnerability due to the improper handling of direct memory access (DMA) buffers on EX4300 switches on Juniper Networks Junos OS allows an attacker sending specific unicast frames to trigger a Denial of Service (DoS) condition by exhausting DMA buffers, causing the FPC to crash and the device to restart. The DMA buffer leak is seen when receiving these specific, valid unicast frames on an interface without Layer 2 Protocol Tunneling (L2PT) or dot1x configured. Interfaces with either L2PT or dot1x configured are not vulnerable to this issue. When this issue occurs, DMA buffer usage keeps increasing and the following error log messages may be observed: Apr 14 14:29:34.360 /kernel: pid 64476 (pfex_junos), uid 0: exited on signal 11 (core dumped) Apr 14 14:29:33.790 init: pfe-manager (PID 64476) terminated by signal number 11. Core dumped! The DMA buffers on the FPC can be monitored by the executing vty command 'show heap': ID Base Total(b) Free(b) Used(b) % Name -- ---------- ----------- ----------- ----------- --- ----------- 0 4a46000 268435456 238230496 30204960 11 Kernel 1 18a46000 67108864 17618536 49490328 73 Bcm_sdk 2 23737000 117440512 18414552 99025960 84 DMA buf <<<<< keeps increasing 3 2a737000 16777216 16777216 0 0 DMA desc This issue affects Juniper Networks Junos OS on the EX4300: 17.3 versions prior to 17.3R3-S11; 17.4 versions prior to 17.4R2-S13, 17.4R3-S4; 18.1 versions prior to 18.1R3-S12; 18.2 versions prior to 18.2R2-S8, 18.2R3-S7; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R1-S8, 18.4R2-S7, 18.4R3-S7; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3-S4; 19.2 versions prior to 19.2R1-S6, 19.2R3-S2; 19.3 versions prior to 19.3R3-S2; 19.4 versions prior to 19.4R2-S3, 19.4R3-S1; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R2-S1, 20.2R3; 20.3 versions prior to 20.3R1-S1, 20.3R2.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
内存缓冲区边界内操作的限制不恰当
Source: CVE Program / CVE List V5
Vulnerability Title
Juniper Networks Junos OS 缓冲区错误漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Juniper Networks Junos OS是美国瞻博网络（Juniper Networks）公司的一套专用于该公司的硬件设备的网络操作系统。该操作系统提供了安全编程接口和Junos SDK。 Junos OS 存在缓冲区错误漏洞，该漏洞允许远程攻击者执行拒绝服务(DoS)攻击。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| Juniper Networks | Junos OS | 17.3 ~ 17.3R3-S11 | - |
|
II. Public POCs for CVE-2021-0242
| # | POC Description | Source Link | Shenlong Link |
|---|
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Vendor Advisories for CVE-2021-0242 (1)
-
https://kb.juniper.net/JSA11135 x_refsource_MISC
Same Patch Batch · Juniper Networks · 2021-04-22 · 53 CVEs total
| CVE-2021-0248 | 10.0 CRITICAL | NFX Series: Hard-coded credentials allow an attacker to take control of any instance throu |
| CVE-2021-0254 | 9.8 CRITICAL | Junos OS: Remote code execution vulnerability in overlayd service |
| CVE-2021-0275 | 8.8 HIGH | Junos OS: J-Web: Cross-site scripting attack allows an attacker to gain control of another |
| CVE-2021-0268 | 8.8 HIGH | Junos OS: J-Web has an Improper Neutralization of CRLF Sequences in its HTTP Headers which |
| CVE-2021-0269 | 8.8 HIGH | Junos OS: J-Web can be compromised through reflected client-side HTTP parameter pollution |
| CVE-2021-0251 | 8.6 HIGH | Junos OS: MX Series with MS-PIC, MS-SPC3, MS-MIC or MS-MPC: The BRAS Subscriber Services s |
| CVE-2021-0249 | 8.1 HIGH | Junos OS: SRX Series: A remote attacker may be able to cause a PFE buffer overflow to arbi |
| CVE-2021-0266 | 8.1 HIGH | cSRX: Use of Hard-coded Cryptographic Keys allows an attacker to take control of the devic |
| CVE-2021-0265 | 8.1 HIGH | Contrail Insights: The REST API implementation allows an unauthenticated remote attacker t |
| CVE-2021-0252 | 7.8 HIGH | Junos OS: NFX Series: Local Code Execution Vulnerability in JDMD Leads to Privilege Escala |
| CVE-2021-0245 | 7.8 HIGH | Junos OS: Junos Fusion: Hard-coded credentials on satellite devices allows a locally authe |
| CVE-2021-0253 | 7.8 HIGH | Junos OS: NFX Series: Local Command Execution Vulnerability in JDMD Leads to Privilege Esc |
| CVE-2021-0270 | 7.5 HIGH | Junos OS: PTX Series, QFX10K Series: A PTX/QFX FPC may restart unexpectedly with the "inli |
| CVE-2021-0227 | 7.5 HIGH | Junos OS: SRX Series: Denial of Service in J-Web upon receipt of crafted HTTP packets |
| CVE-2021-0233 | 7.5 HIGH | Junos OS: ACX500 Series, ACX4000 Series: Denial of Service due to FFEB crash while process |
| CVE-2021-0230 | 7.5 HIGH | Junos OS: SRX Series: Memory leak when querying Aggregated Ethernet (AE) interface statist |
| CVE-2021-0250 | 7.5 HIGH | Junos OS and Junos OS Evolved: An attacker sending a specific crafted BGP update message w |
| CVE-2021-0261 | 7.5 HIGH | Junos OS: Denial of Service vulnerability in J-Web and web based (HTTP/HTTPS) services cau |
| CVE-2021-0267 | 7.4 HIGH | Junos OS: Receipt of a crafted DHCP packet will cause the jdhcpd DHCP service to core. |
| CVE-2021-0232 | 7.4 HIGH | Paragon Active Assurance: Authentication bypass vulnerability in Control Center |
Showing top 20 of 53 CVEs. View all on vendor page → →
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V. Comments for CVE-2021-0242
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