CVE-2021-31379— Junos OS: MX Series: MPC 7/8/9/10/11 cards with MAP-E: PFE halts when an attacker sends malformed IPv4 or IPv6 traffic inside the MAP-E tunnel.
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。 Juniper Networks Junos OS 存在安全漏洞，该漏洞源于Juniper Networks Junos OS 的 MAP-E 自动隧道机制中的行为顺序不正确漏洞允许攻击者发送某些格式错误的 IPv4 或 IPv6 数据包，从而导致对设备上的 PFE 进行拒绝服务 (DoS)，从而导致 PFE
Possible ATT&CK Techniques 1 AI
T1499 · Endpoint Denial of Service
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I. Basic Information for CVE-2021-31379
Vulnerability Information
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Vulnerability Title
Junos OS: MX Series: MPC 7/8/9/10/11 cards with MAP-E: PFE halts when an attacker sends malformed IPv4 or IPv6 traffic inside the MAP-E tunnel.
Source: CVE Program / CVE List V5
Vulnerability Description
An Incorrect Behavior Order vulnerability in the MAP-E automatic tunneling mechanism of Juniper Networks Junos OS allows an attacker to send certain malformed IPv4 or IPv6 packets to cause a Denial of Service (DoS) to the PFE on the device which is disabled as a result of the processing of these packets. Continued receipt and processing of these malformed IPv4 or IPv6 packets will create a sustained Denial of Service (DoS) condition. This issue only affects MPC 7/8/9/10/11 cards, when MAP-E IP reassembly is enabled on these cards. An indicator of compromise is the output: FPC ["FPC ID" # e.g. "0"] PFE #{PFE ID # e.g. "1"] : Fabric Disabled Example: FPC 0 PFE #1 : Fabric Disabled when using the command: show chassis fabric fpcs An example of a healthy result of the command use would be: user@device-re1> show chassis fabric fpcs Fabric management FPC state: FPC 0 PFE #0 Plane 0: Plane enabled Plane 1: Plane enabled Plane 2: Plane enabled Plane 3: Plane enabled Plane 4: Plane enabled Plane 5: Plane enabled Plane 6: Plane enabled Plane 7: Plane enabled This issue affects: Juniper Networks Junos OS on MX Series with MPC 7/8/9/10/11 cards, when MAP-E IP reassembly is enabled on these cards. 17.2 version 17.2R1 and later versions; 17.3 versions prior to 17.3R3-S9; 17.4 versions prior to 17.4R2-S12, 17.4R3-S3; 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R2-S6, 18.2R3-S3; 18.3 versions prior to 18.3R2-S4, 18.3R3-S1; 18.4 versions prior to 18.4R1-S8, 18.4R2-S5, 18.4R3; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S5, 19.3R3. This issue does not affect Juniper Networks Junos OS versions prior to 17.2R1.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
不正确的行为次序
Source: CVE Program / CVE List V5
Vulnerability Title
Juniper Networks Junos OS 安全漏洞
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。 Juniper Networks Junos OS 存在安全漏洞，该漏洞源于Juniper Networks Junos OS 的 MAP-E 自动隧道机制中的行为顺序不正确漏洞允许攻击者发送某些格式错误的 IPv4 或 IPv6 数据包，从而导致对设备上的 PFE 进行拒绝服务 (DoS)，从而导致 PFE
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 | unspecified ~ 17.2R1 | - |
|
II. Public POCs for CVE-2021-31379
| # | POC Description | Source Link | Shenlong Link |
|---|
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Vendor Advisories for CVE-2021-31379 (2)
-
https://kb.juniper.net/JSA11247 x_refsource_CONFIRM
Same Patch Batch · Juniper Networks · 2021-10-19 · 42 CVEs total
| CVE-2021-31349 | 9.8 CRITICAL | Session Smart Router: Authentication Bypass Vulnerability |
| CVE-2021-31385 | 8.8 HIGH | Junos OS: J-Web: A path traversal vulnerability allows an authenticated attacker to elevat |
| CVE-2021-31372 | 8.8 HIGH | Junos OS: J-Web allows a locally authenticated attacker to escalate their privileges to ro |
| CVE-2021-31373 | 8.0 HIGH | Junos OS: SRX Series: Persistent XSS vulnerability in J-Web |
| CVE-2021-31355 | 8.0 HIGH | Junos OS: Stored Cross-Site Scripting (XSS) vulnerability in captive portal |
| CVE-2021-31359 | 7.8 HIGH | Junos OS and Junos OS Evolved: Local Privilege Escalation vulnerability |
| CVE-2021-31358 | 7.8 HIGH | Junos OS Evolved: shell-injection vulnerabilities in evo_sftp UI wrapper script |
| CVE-2021-31357 | 7.8 HIGH | Junos OS Evolved: shell-injection vulnerabilities in evo_tcpdump UI wrapper script |
| CVE-2021-31356 | 7.8 HIGH | Junos OS Evolved: Multiple shell-injection vulnerabilities in EVO UI wrapper scripts |
| CVE-2021-31368 | 7.5 HIGH | Junos OS: EX2300 Series, EX3400 Series, and ACX710 might become unresponsive if the out-of |
| CVE-2021-31374 | 7.5 HIGH | Junos OS and Junos OS Evolved: RPD crash while processing a specially crafted BGP UPDATE o |
| CVE-2021-31376 | 7.5 HIGH | Junos OS: ACX Series: Packet Forwarding Engine manager (FXPC) process crashes when process |
| CVE-2021-31353 | 7.5 HIGH | Junos OS and Junos OS Evolved: RPD core upon receipt of specific BGP update |
| CVE-2021-31351 | 7.5 HIGH | Junos OS: MX Series: Receipt of specific packet on MS-MPC/MS-MIC causes line card reset |
| CVE-2021-31350 | 7.5 HIGH | Junos OS and Junos OS Evolved: Privilege escalation vulnerability in Juniper Extension Too |
| CVE-2021-31383 | 7.5 HIGH | Junos OS and Junos OS Evolved: In Point to MultiPoint (P2MP) scenarios receipt of various |
| CVE-2021-0299 | 7.5 HIGH | Junos OS: Kernel crash (vmcore) upon receipt of a malformed IPv6 packet |
| CVE-2021-0296 | 7.4 HIGH | CTPView: HSTS not being enforced on CTPView server. |
| CVE-2021-31384 | 7.2 HIGH | Junos OS: SRX Series: Under a specific device configuration an attacker can access the dev |
| CVE-2021-31375 | 7.2 HIGH | Junos OS: Receipt of a specific BGP update may cause RPKI policy-checks to be bypassed |
Showing top 20 of 42 CVEs. View all on vendor page → →
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V. Comments for CVE-2021-31379
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