ghsa-393v-j9q3-p63r
Vulnerability from github
An Improper Check for Unusual or Exceptional Conditions vulnerability in the pfe (packet forwarding engine) of Juniper Networks Junos OS on MX Series causes a port within a pool to be blocked leading to Denial of Service (DoS).
In a DS-Lite (Dual-Stack Lite) and NAT (Network Address Translation) scenario, when crafted IPv6 traffic is received and prefix-length is set to 56, the ports assigned to the user will not be freed. Eventually, users cannot establish new connections. Affected FPC/PIC need to be manually restarted to recover. Following is the command to identify the issue:
user@host> show services nat source port-block Host_IP External_IP Port_Block Ports_Used/ Block_State/ Range Ports_Total Left_Time(s) 2001:: x.x.x.x 58880-59391 256/256*1 Active/- >>>>>>>>port still usedThis issue affects Junos OS on MX Series:
- from 21.2 before 21.2R3-S8,
- from 21.4 before 21.4R3-S7,
- from 22.1 before 22.1R3-S6,
- from 22.2 before 22.2R3-S4,
- from 22.3 before 22.3R3-S3,
- from 22.4 before 22.4R3-S2,
- from 23.2 before 23.2R2-S1,
- from 23.4 before 23.4R1-S2, 23.4R2.
This issue does not affect versions before 20.2R1.
{
"affected": [],
"aliases": [
"CVE-2025-21594"
],
"database_specific": {
"cwe_ids": [
"CWE-754"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-04-09T20:15:25Z",
"severity": "HIGH"
},
"details": "An Improper Check for Unusual or Exceptional Conditions vulnerability in the pfe (packet forwarding engine) of Juniper Networks Junos OS on MX Series causes a port within a pool to be blocked leading to Denial of Service (DoS).\n\nIn a DS-Lite (Dual-Stack Lite) and NAT (Network Address Translation) scenario, when crafted IPv6 traffic is received and\u00a0prefix-length is set to 56,\u00a0the ports assigned to the user will not be freed.\u00a0 Eventually, users cannot establish new connections. Affected FPC/PIC need to be manually restarted to recover.\nFollowing is the command to identify the issue:\u00a0\n\n\n\u00a0 \u00a0 user@host\u003e show services nat source port-block\u00a0\n\u2003\u2003\u2003\u2003Host_IP \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 External_IP \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Port_Block\u00a0 \u00a0 \u00a0 Ports_Used/ \u00a0 \u00a0 \u00a0 Block_State/\n\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Range \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Ports_Total \u00a0 \u00a0 \u00a0 Left_Time(s)\n\u2003\u2003\u2003\u20032001::\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 x.x.x.x\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a058880-59391\u00a0 \u00a0 \u00a0256/256*1\u00a0 \u00a0 \u00a0 \u00a0 \u00a0Active/- \u00a0 \u00a0 \u00a0 \u003e\u003e\u003e\u003e\u003e\u003e\u003e\u003eport still usedThis issue affects Junos OS on MX Series:\u00a0\n\n * from 21.2 before 21.2R3-S8,\u00a0\n * from 21.4 before 21.4R3-S7,\u00a0\n * from 22.1 before 22.1R3-S6,\u00a0\n * from 22.2 before 22.2R3-S4,\u00a0\n * from 22.3 before 22.3R3-S3,\u00a0\n * from 22.4 before 22.4R3-S2,\u00a0\n * from 23.2 before 23.2R2-S1,\u00a0\n * from 23.4 before 23.4R1-S2, 23.4R2.\n\n\nThis issue does not affect versions before 20.2R1.",
"id": "GHSA-393v-j9q3-p63r",
"modified": "2025-04-09T21:31:43Z",
"published": "2025-04-09T21:31:43Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-21594"
},
{
"type": "WEB",
"url": "https://supportportal.juniper.net/JSA96449"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/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:X/R:U/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.