// For flags

CVE-2021-29518

Session operations in eager mode lead to null pointer dereferences

Severity Score

7.8
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

1
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

TensorFlow is an end-to-end open source platform for machine learning. In eager mode (default in TF 2.0 and later), session operations are invalid. However, users could still call the raw ops associated with them and trigger a null pointer dereference. The implementation(https://github.com/tensorflow/tensorflow/blob/eebb96c2830d48597d055d247c0e9aebaea94cd5/tensorflow/core/kernels/session_ops.cc#L104) dereferences the session state pointer without checking if it is valid. Thus, in eager mode, `ctx->session_state()` is nullptr and the call of the member function is undefined behavior. The fix will be included in TensorFlow 2.5.0. We will also cherrypick this commit on TensorFlow 2.4.2, TensorFlow 2.3.3, TensorFlow 2.2.3 and TensorFlow 2.1.4, as these are also affected and still in supported range.

TensorFlow es una plataforma de código abierto de extremo a extremo para el aprendizaje automático. En el modo eager (predeterminado en TF versiones 2.0 y posteriores), las operaciones de sesión no son válidas. Sin embargo, los usuarios aún pueden llamar a las operaciones sin procesar asociadas con ellos y activar una desreferencia de puntero null. La implementación (https://github.com/tensorflow/tensorflow/blob/eebb96c2830d48597d055d247c0e9aebaea94cd5/tensorflow/core/kernels/session_ops.cc#L104) elimina las referencias al puntero de estado de la sesión sin comprobar si es válido. Por lo tanto, en modo eager, "ctx-)session_state()" es nullptr y la llamada de la función miembro es un comportamiento indefinido. La corrección será incluída en TensorFlow versión 2.5.0. También seleccionaremos este commit en TensorFlow versión 2.4.2, TensorFlow versión 2.3.3, TensorFlow versión 2.2.3 y TensorFlow versión 2.1.4, ya que estos también están afectados y aún están en el rango admitido

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Attack Vector
Local
Attack Complexity
High
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low
Attack Vector
Local
Attack Complexity
Low
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2021-03-30 CVE Reserved
  • 2021-05-14 CVE Published
  • 2023-03-08 EPSS Updated
  • 2024-08-03 CVE Updated
  • 2024-08-03 First Exploit
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
CWE
  • CWE-476: NULL Pointer Dereference
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Google
Search vendor "Google"
 Tensorflow
Search vendor "Google" for product "Tensorflow"
 < 2.1.4
Search vendor "Google" for product "Tensorflow" and version " < 2.1.4"
-
Affected
Google
Search vendor "Google"
 Tensorflow
Search vendor "Google" for product "Tensorflow"
 >= 2.2.0 < 2.2.3
Search vendor "Google" for product "Tensorflow" and version " >= 2.2.0 < 2.2.3"
-
Affected
Google
Search vendor "Google"
 Tensorflow
Search vendor "Google" for product "Tensorflow"
 >= 2.3.0 < 2.3.3
Search vendor "Google" for product "Tensorflow" and version " >= 2.3.0 < 2.3.3"
-
Affected
Google
Search vendor "Google"
 Tensorflow
Search vendor "Google" for product "Tensorflow"
 >= 2.4.0 < 2.4.2
Search vendor "Google" for product "Tensorflow" and version " >= 2.4.0 < 2.4.2"
-
Affected