When booting a Zync-7000 SOC device from nand flash memory, the nand driver in the ROM does not validate the inputs when reading in any par…

published 2021-03-15 5y ago modified 2026-06-17 4mo ago also EUVD-2021-13973

cvss: 6.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 33%
public exploits: 0; none known

When booting a Zync-7000 SOC device from nand flash memory, the nand driver in the ROM does not validate the inputs when reading in any parameters in the nand’s parameter page. IF a field read in from the parameter page is too large, this causes a buffer overflow that could lead to arbitrary code execution. Physical access and modification of the board assembly on which the Zynq-7000 SoC device mounted is needed to replace the original NAND flash memory with a NAND flash emulation device for this attack to be successful.

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Exploit prediction

0.39% chance of exploitation in the next 30 days, higher than 33% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.1	6.8	CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	4.6	AV:L/AC:L/Au:N/C:P/I:P/A:P

Classification

Weakness

CWE-120 Buffer Copy without Checking Size of Input

References

xilinx.com /products/silicon-devices/soc/zynq-7000.html
product, vendor-advisory
xilinx.com /support/answers/76201.html
vendor-advisory
onfi.org /specifications
not-applicable

Sources

CVE List CVE-2021-27208
NVD CVE-2021-27208

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