A Heap-based Buffer Overflow vulnerability in the Routing Protocol Daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, network based attacker to cause a Denial of Service (DoS).
If an attacker sends a specific BGP UPDATE message to the device, this will cause a memory overwrite and therefore an RPD crash and restart in the backup Routing Engine (RE). Continued receipt of these packets will cause a sustained Denial of Service (DoS) condition in the backup RE.
The primary RE is not impacted by this issue and there is no impact on traffic.
This issue only affects devices with NSR enabled.
Note: NSR is not supported on the SRX Series and is therefore not affected by this vulnerability.
This issue requires an attacker to have an established BGP session to a system affected by the issue. This issue affects both eBGP and iBGP implementations.
This issue affects:
Juniper Networks Junos OS
- All versions earlier than 20.4R3-S9;
- 21.2 versions earlier than 21.2R3-S7;
- 21.3 versions earlier than 21.3R3-S5;
- 21.4 versions earlier than 21.4R3-S5;
- 22.1 versions earlier than 22.1R3-S4;
- 22.2 versions earlier than 22.2R3-S2;
- 22.3 versions earlier than 22.3R3-S1;
- 22.4 versions earlier than 22.4R2-S2, 22.4R3;
- 23.1 versions earlier than 23.1R2;
- 23.2 versions earlier than 23.2R1-S2, 23.2R2.
Juniper Networks Junos OS Evolved
- All versions earlier than 21.3R3-S5-EVO;
- 21.4-EVO versions earlier than 21.4R3-S5-EVO;
- 22.1-EVO versions earlier than 22.1R3-S4-EVO;
- 22.2-EVO versions earlier than 22.2R3-S2-EVO;
- 22.3-EVO versions later than 22.3R1-EVO;
- 22.4-EVO versions earlier than 22.4R2-S2-EVO, 22.4R3-EVO;
- 23.1-EVO versions earlier than 23.1R2-EVO;
- 23.2-EVO versions earlier than 23.2R1-S2-EVO, 23.2R2-EVO.
Weakness
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
Affected Software
| Name |
Vendor |
Start Version |
End Version |
| Junos |
Juniper |
20.4 (including) |
20.4 (including) |
| Junos |
Juniper |
20.4-r1 (including) |
20.4-r1 (including) |
| Junos |
Juniper |
20.4-r1-s1 (including) |
20.4-r1-s1 (including) |
| Junos |
Juniper |
20.4-r2 (including) |
20.4-r2 (including) |
| Junos |
Juniper |
20.4-r2-s1 (including) |
20.4-r2-s1 (including) |
| Junos |
Juniper |
20.4-r2-s2 (including) |
20.4-r2-s2 (including) |
| Junos |
Juniper |
20.4-r3 (including) |
20.4-r3 (including) |
| Junos |
Juniper |
20.4-r3-s1 (including) |
20.4-r3-s1 (including) |
| Junos |
Juniper |
20.4-r3-s2 (including) |
20.4-r3-s2 (including) |
| Junos |
Juniper |
20.4-r3-s3 (including) |
20.4-r3-s3 (including) |
| Junos |
Juniper |
20.4-r3-s4 (including) |
20.4-r3-s4 (including) |
| Junos |
Juniper |
20.4-r3-s5 (including) |
20.4-r3-s5 (including) |
| Junos |
Juniper |
20.4-r3-s6 (including) |
20.4-r3-s6 (including) |
| Junos |
Juniper |
20.4-r3-s7 (including) |
20.4-r3-s7 (including) |
| Junos |
Juniper |
20.4-r3-s8 (including) |
20.4-r3-s8 (including) |
Potential Mitigations
- Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking.
- D3-SFCV (Stack Frame Canary Validation) from D3FEND [REF-1334] discusses canary-based detection in detail.
- Run or compile the software using features or extensions that randomly arrange the positions of a program’s executable and libraries in memory. Because this makes the addresses unpredictable, it can prevent an attacker from reliably jumping to exploitable code.
- Examples include Address Space Layout Randomization (ASLR) [REF-58] [REF-60] and Position-Independent Executables (PIE) [REF-64]. Imported modules may be similarly realigned if their default memory addresses conflict with other modules, in a process known as “rebasing” (for Windows) and “prelinking” (for Linux) [REF-1332] using randomly generated addresses. ASLR for libraries cannot be used in conjunction with prelink since it would require relocating the libraries at run-time, defeating the whole purpose of prelinking.
- For more information on these techniques see D3-SAOR (Segment Address Offset Randomization) from D3FEND [REF-1335].
References