CVE-2026-21914
published 2026-01-15CVE-2026-21914: An Improper Locking vulnerability in the GTP plugin of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a…
PriorityP348high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.30%
21.8th percentile
An Improper Locking vulnerability in the GTP plugin of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (Dos).
If an SRX Series device receives a specifically malformed GPRS Tunnelling Protocol (GTP) Modify Bearer Request message, a lock is acquired and never released. This results in other threads not being able to acquire a lock themselves, causing a watchdog timeout leading to FPC crash and restart. This issue leads to a complete traffic outage until the device has automatically recovered.
This issue affects Junos OS on SRX Series:
* all versions before 22.4R3-S8,
* 23.2 versions before 23.2R2-S5,
* 23.4 versions before 23.4R2-S6,
* 24.2 versions before 24.2R2-S3,
* 24.4 versions before 24.4R2-S2,
* 25.2 versions before 25.2R1-S1, 25.2R2.
Affected
15 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| juniper | junos | < 22.4 | 22.4 |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos_os | — | — |
| juniper | srx_series | — | — |
| juniper_networks | junos_os | < 22.4R3-S8 | 22.4R3-S8 |
| juniper_networks | junos_os | >= 23.2 < 23.2R2-S5 | 23.2R2-S5 |
| juniper_networks | junos_os | >= 23.4 < 23.4R2-S6 | 23.4R2-S6 |
| juniper_networks | junos_os | >= 24.2 < 24.2R2-S3 | 24.2R2-S3 |
| juniper_networks | junos_os | >= 24.4 < 24.4R2-S2 | 24.4R2-S2 |
| juniper_networks | junos_os | >= 25.2 < 25.2R1-S1, 25.2R2 | 25.2R1-S1, 25.2R2 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv4.08.7HIGHCVSS: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:Y/R:A/V:X/RE:M/U:X
Stop checking back — get the weekly exploitation signal.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
GHSA
GHSA-w5fv-m4rq-pgg2: An Improper Locking vulnerability in the GTP plugin of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to ca
ghsa_unreviewed·2026-01-15
CVE-2026-21914 [HIGH] CWE-667 GHSA-w5fv-m4rq-pgg2: An Improper Locking vulnerability in the GTP plugin of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to ca
An Improper Locking vulnerability in the GTP plugin of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (Dos).
If an SRX Series device receives a specifically malformed GPRS Tunnelling Protocol (GTP) Modify Bearer Request message, a lock is acquired and never released. This results in other threads not being able to acquire a lock themselves, causing a watchdog timeout leading to FPC crash and restart. This issue leads to a complete traffic outage until the device has automatically recovered.
This issue affects Junos OS on SRX Series:
* all versions before 22.4R3-S8,
* 23.2 versions before 23.2R2-S5,
* 23.4 versions before 23.4R2-S6,
* 24.2 versions before 24.2R2-S3,
* 24.4 versions before 24.4R2-S2,
* 25.2 versions b
Juniper
CVE-2026-21914: An Improper Locking vulnerability in the GTP plugin of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to ca
vendor_juniper·2026-01-15·CVSS 7.5
CVE-2026-21914 [HIGH] CWE-667 CVE-2026-21914: An Improper Locking vulnerability in the GTP plugin of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to ca
CVE-2026-21914: An Improper Locking vulnerability in the GTP plugin of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (Dos).
If an SRX Series device receives a specifically malformed GPRS Tunnelling Protocol (GTP) Modify Bearer Request message, a lock is acquired and never released. This results in other threads not being able to acquire a lock themselves, causing a watchdog timeout leading to FPC crash and restart. This issue leads to a complete traffic outage until the device has automatically recovered.
This issue affects Junos OS on SRX Series:
* all versions before 22.4R3-S8,
* 23.2 versions before 23.2R2-S5,
* 23.4 versions before 23.4R2-S6,
* 24.2 versions before 24.2R2-S3,
* 24.4 versions before 24.4R2-S2,
*
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-01-15
Published