A Loop with Unreachable Exit Condition ('Infinite Loop') vulnerability in the SIP application layer gateway (ALG) of Juniper Networks Junos OS on SRX Series and MX Series with MX-SPC3 or MS-MPC allows an unauthenticated network-based attacker sending specific SIP messages over TCP to crash the flow management process, leading to a Denial of Service (DoS).
On SRX Series, and MX Series with MX-SPC3 or MS-MPC service cards, receipt of multiple SIP messages causes the SIP headers to be parsed incorrectly, eventually causing a continuous loop and leading to a watchdog timer expiration, crashing the flowd process on SRX Series and MX Series with MX-SPC3, or mspmand process on MX Series with MS-MPC.
This issue only occurs over TCP. SIP messages sent over UDP cannot trigger this issue.
This issue affects Junos OS on SRX Series and MX Series with MX-SPC3 and MS-MPC:
* all versions before 21.2R3-S10,
* from 21.4 before 21.4R3-S12,
* from 22.4 before 22.4R3-S8,
* from 23.2 before 23.2R2-S5,
* from 23.4 before 23.4R2-S6,
* from 24.2 before 24.2R2-S3,
* from 24.4 before 24.4R2-S1,
* from 25.2 before 25.2R1-S1, 25.2R2.
References
| Link | Resource |
|---|---|
| https://kb.juniper.net/JSA106004 | Vendor Advisory |
| https://supportportal.juniper.net/JSA106004 | Vendor Advisory |
Configurations
Configuration 1 (hide)
| AND |
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History
23 Jan 2026, 19:40
| Type | Values Removed | Values Added |
|---|---|---|
| References | () https://kb.juniper.net/JSA106004 - Vendor Advisory | |
| References | () https://supportportal.juniper.net/JSA106004 - Vendor Advisory | |
| First Time |
Juniper srx5600
Juniper mx10004 Juniper mx304 Juniper srx1500 Juniper Juniper mx240 Juniper mx10008 Juniper mx480 Juniper srx320 Juniper srx1600 Juniper srx5400 Juniper junos Juniper srx2300 Juniper srx380 Juniper srx4120 Juniper mx2020 Juniper srx5800 Juniper srx300 Juniper srx4300 Juniper srx345 Juniper srx4200 Juniper srx340 Juniper mx2008 Juniper mx960 Juniper mx2010 Juniper srx4100 Juniper srx4700 Juniper srx4600 Juniper mx204 |
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| CPE | cpe:2.3:o:juniper:junos:23.2:r2-s3:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.4:r2-s1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.4:-:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:r3-s5:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r3-s10:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r2-s2:*:*:*:*:*:* cpe:2.3:h:juniper:mx2020:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:srx5600:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r3-s1:*:*:*:*:*:* cpe:2.3:h:juniper:mx304:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:srx380:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.4:r2-s4:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r1-s1:*:*:*:*:*:* cpe:2.3:h:juniper:mx10008:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r3-s4:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r3-s3:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:r3:*:*:*:*:*:* cpe:2.3:h:juniper:srx1500:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:srx1600:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:srx5800:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r3-s11:*:*:*:*:*:* cpe:2.3:h:juniper:srx5400:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.4:r1-s2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r3-s5:*:*:*:*:*:* cpe:2.3:h:juniper:srx2300:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:mx240:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r3-s7:*:*:*:*:*:* cpe:2.3:o:juniper:junos:*:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.2:r2-s1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:r1-s2:*:*:*:*:*:* cpe:2.3:h:juniper:srx340:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.2:r2-s4:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:r3-s4:*:*:*:*:*:* cpe:2.3:h:juniper:srx4600:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r3-s2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r3-s9:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.2:r1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r3:*:*:*:*:*:* cpe:2.3:h:juniper:srx300:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.4:r2-s3:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.4:r2-s5:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:r2-s1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r2-s1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:r3-s7:*:*:*:*:*:* cpe:2.3:o:juniper:junos:25.2:r2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r3-s4:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.4:r1-s1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.2:r1-s2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.2:r1:*:*:*:*:*:* cpe:2.3:h:juniper:srx320:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.4:r2:*:*:*:*:*:* cpe:2.3:h:juniper:srx4200:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.2:-:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.2:-:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.4:-:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.2:r1-s1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r3-s2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:r3-s2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r3-s8:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:r2-s2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.2:r2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:-:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r3:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:r1-s1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.4:r1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.4:r1-s2:*:*:*:*:*:* cpe:2.3:h:juniper:mx10004:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:r3-s1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.2:r2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.4:r2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:25.2:-:*:*:*:*:*:* cpe:2.3:h:juniper:mx204:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r3-s6:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r3-s8:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r1-s2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r3-s9:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r3-s1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.4:r2-s2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.2:r2-s2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.4:r1-s3:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:-:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:r3-s3:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.2:r2-s2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r2-s2:*:*:*:*:*:* cpe:2.3:h:juniper:srx4300:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r2:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.2:r2-s1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:r3-s6:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:r2:*:*:*:*:*:* cpe:2.3:h:juniper:mx2010:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:mx2008:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:mx960:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.4:r1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r3-s7:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r2-s1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:23.2:r1-s2:*:*:*:*:*:* cpe:2.3:h:juniper:srx345:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:srx4700:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r1-s2:*:*:*:*:*:* cpe:2.3:h:juniper:srx4120:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r3-s3:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r1-s1:*:*:*:*:*:* cpe:2.3:h:juniper:mx480:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:22.4:r1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:-:*:*:*:*:*:* cpe:2.3:o:juniper:junos:25.2:r1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.2:r1-s1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.4:r3-s6:*:*:*:*:*:* cpe:2.3:o:juniper:junos:21.2:r3-s5:*:*:*:*:*:* cpe:2.3:h:juniper:srx4100:-:*:*:*:*:*:*:* |
15 Jan 2026, 21:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-01-15 21:16
Updated : 2026-01-23 19:40
NVD link : CVE-2026-21905
Mitre link : CVE-2026-21905
CVE.ORG link : CVE-2026-21905
JSON object : View
Products Affected
juniper
- srx380
- mx2008
- mx10008
- mx304
- srx340
- srx4100
- mx2020
- srx5800
- junos
- srx4300
- mx960
- srx300
- mx480
- mx204
- srx320
- srx4700
- mx2010
- srx345
- srx4200
- mx10004
- srx4120
- srx2300
- srx5400
- mx240
- srx1600
- srx4600
- srx1500
- srx5600
CWE
CWE-835
Loop with Unreachable Exit Condition ('Infinite Loop')