# CVE-2026-21914

## Summary

- **CVE ID:** CVE-2026-21914
- **Severity:** HIGH
- **CVSS Score:** 8.7 (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/AU:Y/R:A/RE:M)
- **CWE:** CWE-667
- **Published:** Jan 15, 2026
- **Last Modified:** Mar 12, 2026

## Description

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 Products

- Juniper Networks — Junos OS (0)
- Juniper Networks — Junos OS (23.2)
- Juniper Networks — Junos OS (23.4)
- Juniper Networks — Junos OS (24.2)
- Juniper Networks — Junos OS (24.4)
- Juniper Networks — Junos OS (25.2)

## References

- [CNA](https://supportportal.juniper.net/JSA106015)
- [CNA](https://kb.juniper.net/JSA106015)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.31%
- **EPSS Percentile:** 23.7

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-10._