CVE Vulnerabilities

CVE-2020-11183

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

Published: Jan 21, 2021 | Modified: Jan 29, 2021
CVSS 3.x
6.7
MEDIUM
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
7.2 HIGH
AV:L/AC:L/Au:N/C:C/I:C/A:C
RedHat/V2
RedHat/V3
Ubuntu

A process can potentially cause a buffer overflow in the display service allowing privilege escalation by executing code as that service in Snapdragon Auto, Snapdragon Connectivity, Snapdragon Consumer IOT, Snapdragon Industrial IOT, Snapdragon Mobile, Snapdragon Voice & Music, Snapdragon Wearables

Weakness

The program copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow.

Affected Software

Name Vendor Start Version End Version
Apq8009 Qualcomm - -
Apq8009w Qualcomm - -
Apq8017 Qualcomm - -
Apq8037 Qualcomm - -
Apq8053 Qualcomm - -
Apq8096au Qualcomm - -
Ar8151 Qualcomm - -
Mdm9206 Qualcomm - -
Mdm9250 Qualcomm - -
Mdm9650 Qualcomm - -
Mdm9655 Qualcomm - -
Msm8909w Qualcomm - -
Msm8917 Qualcomm - -
Msm8920 Qualcomm - -
Msm8937 Qualcomm - -
Msm8940 Qualcomm - -
Msm8953 Qualcomm - -
Msm8996au Qualcomm - -
Pm215 Qualcomm - -
Pm439 Qualcomm - -
Pm660 Qualcomm - -
Pm660a Qualcomm - -
Pm660l Qualcomm - -
Pm8004 Qualcomm - -
Pm8005 Qualcomm - -
Pm855a Qualcomm - -
Pm8909 Qualcomm - -
Pm8916 Qualcomm - -
Pm8937 Qualcomm - -
Pm8940 Qualcomm - -
Pm8953 Qualcomm - -
Pm8996 Qualcomm - -
Pm8998 Qualcomm - -
Pmd9607 Qualcomm - -
Pmd9655 Qualcomm - -
Pmi632 Qualcomm - -
Pmi8937 Qualcomm - -
Pmi8940 Qualcomm - -
Pmi8952 Qualcomm - -
Pmi8994 Qualcomm - -
Pmi8996 Qualcomm - -
Pmi8998 Qualcomm - -
Pmk8001 Qualcomm - -
Pmm855au Qualcomm - -
Pmm8996au Qualcomm - -
Pmx20 Qualcomm - -
Qat3514 Qualcomm - -
Qat3522 Qualcomm - -
Qat3550 Qualcomm - -
Qbt1000 Qualcomm - -
Qbt1500 Qualcomm - -
Qca6174a Qualcomm - -
Qca6310 Qualcomm - -
Qca6320 Qualcomm - -
Qca6564a Qualcomm - -
Qca6564au Qualcomm - -
Qca6574a Qualcomm - -
Qca6574au Qualcomm - -
Qca6595 Qualcomm - -
Qca6595au Qualcomm - -
Qca9367 Qualcomm - -
Qca9377 Qualcomm - -
Qca9379 Qualcomm - -
Qcc1110 Qualcomm - -
Qet4100 Qualcomm - -
Qet4101 Qualcomm - -
Qet4200aq Qualcomm - -
Qet5100 Qualcomm - -
Qfe2080fc Qualcomm - -
Qfe2081fc Qualcomm - -
Qfe2082fc Qualcomm - -
Qfe2101 Qualcomm - -
Qfe2550 Qualcomm - -
Qfe3100 Qualcomm - -
Qfe3440fc Qualcomm - -
Qfe4301 Qualcomm - -
Qfe4302 Qualcomm - -
Qfe4303 Qualcomm - -
Qfe4305 Qualcomm - -
Qfe4308 Qualcomm - -
Qfe4309 Qualcomm - -
Qfe4320 Qualcomm - -
Qfe4373fc Qualcomm - -
Qfe4455fc Qualcomm - -
Qfe4465fc Qualcomm - -
Qln1021aq Qualcomm - -
Qln1030 Qualcomm - -
Qln1031 Qualcomm - -
Qln1035bd Qualcomm - -
Qln1036aq Qualcomm - -
Qpa4340 Qualcomm - -
Qpa4360 Qualcomm - -
Qpa5373 Qualcomm - -
Qpa5460 Qualcomm - -
Qsw8573 Qualcomm - -
Qtc800h Qualcomm - -
Qtc800s Qualcomm - -
Qtc800t Qualcomm - -
Qtc801s Qualcomm - -
Qualcomm215 Qualcomm - -
Rgr7640au Qualcomm - -
Rsw8577 Qualcomm - -
Sd439 Qualcomm - -
Sd450 Qualcomm - -
Sd636 Qualcomm - -
Sd660 Qualcomm - -
Sd710 Qualcomm - -
Sd712 Qualcomm - -
Sd820 Qualcomm - -
Sd821 Qualcomm - -
Sd835 Qualcomm - -
Sdm630 Qualcomm - -
Sdm830 Qualcomm - -
Sdr051 Qualcomm - -
Sdr052 Qualcomm - -
Sdr660 Qualcomm - -
Sdw2500 Qualcomm - -
Sdw3100 Qualcomm - -
Sdx20 Qualcomm - -
Sdx20m Qualcomm - -
Sdx50m Qualcomm - -
Smb1350 Qualcomm - -
Smb1351 Qualcomm - -
Smb1355 Qualcomm - -
Smb1357 Qualcomm - -
Smb1358 Qualcomm - -
Smb1360 Qualcomm - -
Smb1380 Qualcomm - -
Smb231 Qualcomm - -
Wcd9326 Qualcomm - -
Wcd9330 Qualcomm - -
Wcd9335 Qualcomm - -
Wcd9340 Qualcomm - -
Wcd9341 Qualcomm - -
Wcn3615 Qualcomm - -
Wcn3620 Qualcomm - -
Wcn3660b Qualcomm - -
Wcn3680 Qualcomm - -
Wcn3680b Qualcomm - -
Wcn3980 Qualcomm - -
Wcn3990 Qualcomm - -
Wgr7640 Qualcomm - -
Wsa8810 Qualcomm - -
Wsa8815 Qualcomm - -
Wtr2955 Qualcomm - -
Wtr2965 Qualcomm - -
Wtr3905 Qualcomm - -
Wtr3925 Qualcomm - -
Wtr3950 Qualcomm - -
Wtr4905 Qualcomm - -
Wtr5975 Qualcomm - -

Potential Mitigations

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.

  • For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer.

  • Be wary that a language’s interface to native code may still be subject to overflows, even if the language itself is theoretically safe.

  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.

  • Examples include the Safe C String Library (SafeStr) by Messier and Viega [REF-57], and the Strsafe.h library from Microsoft [REF-56]. These libraries provide safer versions of overflow-prone string-handling functions.

  • Run or compile the software using features or extensions that automatically provide a protection mechanism that mitigates or eliminates buffer overflows.

  • For example, certain compilers and extensions provide automatic buffer overflow detection mechanisms that are built into the compiled code. Examples include the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice.

  • Consider adhering to the following rules when allocating and managing an application’s memory:

  • Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.

  • When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”

  • Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.

  • 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].

  • Run the code in a “jail” or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.

  • OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.

  • This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.

  • Be careful to avoid CWE-243 and other weaknesses related to jails.

References