CVE-2021-0254
CVE.org · Published
- Record status
- Published
- Identifier year (not publication year)
- 2021
- Source publication
- Source updated
- Imported by cveboard
- Source snapshot
- cve_2026-10-24_midnight_baseline ·
CNA source text (English)
Junos OS: Remote code execution vulnerability in overlayd service
A buffer size validation vulnerability in the overlayd service of Juniper Networks Junos OS may allow an unauthenticated remote attacker to send specially crafted packets to the device, triggering a partial Denial of Service (DoS) condition, or leading to remote code execution (RCE). Continued receipt and processing of these packets will sustain the partial DoS. The overlayd daemon handles Overlay OAM packets, such as ping and traceroute, sent to the overlay. The service runs as root by default and listens for UDP connections on port 4789. This issue results from improper buffer size validation, which can lead to a buffer overflow. Unauthenticated attackers can send specially crafted packets to trigger this vulnerability, resulting in possible remote code execution. overlayd runs by default in MX Series, ACX Series, and QFX Series platforms. The SRX Series does not support VXLAN and is therefore not vulnerable to this issue. Other platforms are also vulnerable if a Virtual Extensible LAN (VXLAN) overlay network is configured. This issue affects Juniper Networks Junos OS: 15.1 versions prior to 15.1R7-S9; 17.3 versions prior to 17.3R3-S11; 17.4 versions prior to 17.4R2-S13, 17.4R3-S4; 18.1 versions prior to 18.1R3-S12; 18.2 versions prior to 18.2R2-S8, 18.2R3-S7; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R1-S8, 18.4R2-S7, 18.4R3-S7; 19.1 versions prior to 19.1R2-S2, 19.1R3-S4; 19.2 versions prior to 19.2R1-S6, 19.2R3-S2; 19.3 versions prior to 19.3R3-S1; 19.4 versions prior to 19.4R2-S4, 19.4R3-S1; 20.1 versions prior to 20.1R2-S1, 20.1R3; 20.2 versions prior to 20.2R2, 20.2R2-S1, 20.2R3; 20.3 versions prior to 20.3R1-S1.
Scoped product and version facts
Fix information unknown; no fixed version is derived here. Missing information does not prove that no fix exists.
Exploitation unknown; this catalogue does not assess exploitation.
Junos OS
- Vendor
- Juniper Networks
- Product
- Junos OS
- Platforms
- Unknown
- Default status
Unknown
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 15.1 | affected | custom | 15.1R7-S9 | Unavailable | None listed |
| 17.3 | affected | custom | 17.3R3-S11 | Unavailable | None listed |
| 17.4 | affected | custom | 17.4R2-S13, 17.4R3-S4 | Unavailable | None listed |
| 18.1 | affected | custom | 18.1R3-S12 | Unavailable | None listed |
| 18.2 | affected | custom | 18.2R2-S8, 18.2R3-S7 | Unavailable | None listed |
| 18.3 | affected | custom | 18.3R3-S4 | Unavailable | None listed |
| 18.4 | affected | custom | 18.4R1-S8, 18.4R2-S7, 18.4R3-S7 | Unavailable | None listed |
| 19.1 | affected | custom | 19.1R2-S2, 19.1R3-S4 | Unavailable | None listed |
| 19.2 | affected | custom | 19.2R1-S6, 19.2R3-S2 | Unavailable | None listed |
| 19.3 | affected | custom | 19.3R3-S1 | Unavailable | None listed |
| 19.4 | affected | custom | 19.4R2-S4, 19.4R3-S1 | Unavailable | None listed |
| 20.1 | affected | custom | 20.1R2-S1, 20.1R3 | Unavailable | None listed |
| 20.2 | affected | custom | 20.2R2, 20.2R2-S1, 20.2R3 | Unavailable | None listed |
| 20.3 | affected | custom | 20.3R1-S1 | Unavailable | None listed |