Ejecuta análisis estático (SAST) sobre el código buscando el patrón inseguro en el flujo de datos.
Hardware Logic Contains Race Conditions
A hardware race condition occurs when security-critical logic circuits receive signals at slightly different times, creating temporary glitches that can bypass system protections.
What is CWE-1298?
Real-world CVEs caused by CWE-1298
Todavía no hay CVEs públicos enlazados a esta CWE en el catálogo de MITRE.
Ruta del atacante paso a paso
- 1
The code below shows a 2x1 multiplexor using logic gates. Though the code shown below results in the minimum gate solution, it is disjoint and causes glitches.
- 2
The buggy line of code, commented above, results in signal 'z' periodically changing to an unwanted state. Thus, any logic that references signal 'z' may access it at a time when it is in this unwanted state. This line should be replaced with the line shown below in the Good Code Snippet which results in signal 'z' remaining in a continuous, known, state. Reference for the above code, along with waveforms for simulation can be found in the references below.
- 3
This line of code removes the glitch in signal z.
- 4
The example code is taken from the DMA (Direct Memory Access) module of the buggy OpenPiton SoC of HACK@DAC'21. The DMA contains a finite-state machine (FSM) for accessing the permissions using the physical memory protection (PMP) unit. PMP provides secure regions of physical memory against unauthorized access. It allows an operating system or a hypervisor to define a series of physical memory regions and then set permissions for those regions, such as read, write, and execute permissions. When a user tries to access a protected memory area (e.g., through DMA), PMP checks the access of a PMP address (e.g., pmpaddr_i) against its configuration (pmpcfg_i). If the access violates the defined permissions (e.g., CTRL_ABORT), the PMP can trigger a fault or an interrupt. This access check is implemented in the pmp parametrized module in the below code snippet. The below code assumes that the state of the pmpaddr_i and pmpcfg_i signals will not change during the different DMA states (i.e., CTRL_IDLE to CTRL_DONE) while processing a DMA request (via dma_ctrl_reg). The DMA state machine is implemented using a case statement (not shown in the code snippet).
- 5
However, the above code [REF-1394] allows the values of pmpaddr_i and pmpcfg_i to be changed through DMA's input ports. This causes a race condition and will enable attackers to access sensitive addresses that the configuration is not associated with. Attackers can initialize the DMA access process (CTRL_IDLE) using pmpcfg_i for a non-privileged PMP address (pmpaddr_i). Then during the loading state (CTRL_LOAD), attackers can replace the non-privileged address in pmpaddr_i with a privileged address without the requisite authorized access configuration. To fix this issue (see [REF-1395]), the value of the pmpaddr_i and pmpcfg_i signals should be stored in local registers (pmpaddr_reg and pmpcfg_reg at the start of the DMA access process and the pmp module should reference those registers instead of the signals directly. The values of the registers can only be updated at the start (CTRL_IDLE) or the end (CTRL_DONE) of the DMA access process, which prevents attackers from changing the PMP address in the middle of the DMA access process.
Vulnerable Verilog
The code below shows a 2x1 multiplexor using logic gates. Though the code shown below results in the minimum gate solution, it is disjoint and causes glitches.
// 2x1 Multiplexor using logic-gates
module glitchEx(
```
input wire in0, in1, sel,
output wire z
);
wire not_sel;
wire and_out1, and_out2;
assign not_sel = ~sel;
assign and_out1 = not_sel & in0;
assign and_out2 = sel & in1;
// Buggy line of code:
assign z = and_out1 | and_out2; // glitch in signal z
endmodule Secure Verilog
The buggy line of code, commented above, results in signal 'z' periodically changing to an unwanted state. Thus, any logic that references signal 'z' may access it at a time when it is in this unwanted state. This line should be replaced with the line shown below in the Good Code Snippet which results in signal 'z' remaining in a continuous, known, state. Reference for the above code, along with waveforms for simulation can be found in the references below.
assign z <= and_out1 or and_out2 or (in0 and in1); How to prevent CWE-1298
- Architecture and Design Adopting design practices that encourage designers to recognize and eliminate race conditions, such as Karnaugh maps, could result in the decrease in occurrences of race conditions.
- Implementation Logic redundancy can be implemented along security critical paths to prevent race conditions. To avoid metastability, it is a good practice in general to default to a secure state in which access is not given to untrusted agents.
How to detect CWE-1298
Ejecuta pruebas dinámicas de seguridad de aplicaciones (DAST) contra el endpoint en vivo.
Vigila los logs en tiempo de ejecución para detectar trazas de excepción inusuales, entradas malformadas o intentos de bypass de autorización.
Revisión de código: marca cualquier código nuevo que maneje entrada desde esta superficie sin usar los helpers validados del framework.
Plexicus detecta automáticamente CWE-1298 y abre un PR de corrección en menos de 60 segundos.
Codex Remedium escanea cada commit, identifica esta debilidad concreta y entrega un pull request listo para revisión con el parche. Sin tickets. Sin traspasos.
Frequently asked questions
¿Qué es CWE-1298?
A hardware race condition occurs when security-critical logic circuits receive signals at slightly different times, creating temporary glitches that can bypass system protections.
¿Qué gravedad tiene CWE-1298?
MITRE no ha publicado una calificación de probabilidad de explotación para esta debilidad. Trátala como de impacto medio hasta que tu modelo de amenazas demuestre lo contrario.
¿Qué lenguajes o plataformas se ven afectados por CWE-1298?
MITRE lists the following affected platforms: Verilog, VHDL, System on Chip.
¿Cómo puedo prevenir CWE-1298?
Adopting design practices that encourage designers to recognize and eliminate race conditions, such as Karnaugh maps, could result in the decrease in occurrences of race conditions. Logic redundancy can be implemented along security critical paths to prevent race conditions. To avoid metastability, it is a good practice in general to default to a secure state in which access is not given to untrusted agents.
¿Cómo detecta y corrige Plexicus CWE-1298?
El motor SAST de Plexicus detecta la firma de flujo de datos para CWE-1298 en cada commit. Cuando hay coincidencia, nuestro agente Codex Remedium abre un PR de corrección con el código corregido, las pruebas y un resumen de una línea para el revisor.
¿Dónde puedo aprender más sobre CWE-1298?
MITRE publica la definición canónica en https://cwe.mitre.org/data/definitions/1298.html. También puedes consultar la documentación de OWASP y NIST para guías relacionadas.
Weaknesses related to CWE-1298
Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
A race condition occurs when multiple processes or threads access a shared resource simultaneously without proper coordination, creating a…
Race Condition for Write-Once Attributes
This vulnerability occurs when an untrusted software component wins a race condition and writes to a hardware register before the trusted…
Signal Handler Race Condition
A signal handler race condition occurs when a program's signal handling routine is vulnerable to timing issues, allowing its state to be…
Race Condition within a Thread
This vulnerability occurs when two or more threads within the same application access and manipulate a shared resource (like a variable,…
Time-of-check Time-of-use (TOCTOU) Race Condition
This vulnerability occurs when a program verifies a resource's state (like a file's permissions or existence) but then uses it after that…
Context Switching Race Condition
This vulnerability occurs when an application switches between different security contexts (like privilege levels or domains) using a…
Race Condition During Access to Alternate Channel
A race condition occurs when an application opens a secondary communication channel intended for an authorized user, but fails to secure…
Permission Race Condition During Resource Copy
This vulnerability occurs when a system copies a file or resource but delays setting its final permissions until the entire copy operation…
Further reading
- MITRE — CWE-1298 oficial https://cwe.mitre.org/data/definitions/1298.html
- FPGA designs with Verilog (section 7.4 Glitches) https://verilogguide.readthedocs.io/en/latest/verilog/fsm.html
- Non-Blocking Assignments in Verilog Synthesis, Coding Styles that Kill! http://www.sunburst-design.com/papers/CummingsSNUG2000SJ_NBA.pdf
- dma.sv https://github.com/HACK-EVENT/hackatdac21/blob/main/piton/design/chip/tile/ariane/src/dma/dma.sv
- Fix for dma.sv https://github.com/HACK-EVENT/hackatdac21/blob/cwe_1298_in_dma/piton/design/chip/tile/ariane/src/dma/dma.sv
Deja de pagar por desarrollador.
Empieza a cerrar el bucle.
Plexicus es el ASPM nativo de IA que escanea, filtra, corrige, pentestea y explica — de forma autónoma. Desarrolladores ilimitados, repos ilimitados, acciones de IA de uso justo. Nivel gratuito real, €269/mo anual cuando estés listo.