SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2020-13131

A malicious PIV token can misreport the returned length fields during RSA key generation.

MEDIUM 4.3EPSS 0.49%

Does this matter?

Lower severity and a low EPSS score (0.49%). Track it; it rarely justifies an emergency change on its own.

Description

An issue was discovered in Yubico libykpiv before 2.1.0. lib/util.c in this library (which is included in yubico-piv-tool) does not properly check embedded length fields during device communication. A malicious PIV token can misreport the returned length fields during RSA key generation. This will cause stack memory to be copied into heap allocated memory that gets returned to the caller. The leaked memory could include PINs, passwords, key material, and other sensitive information depending on the integration. During further processing by the caller, this information could leak across trust boundaries. Note that RSA key generation is triggered by the host and cannot directly be triggered by the token.

CVSS 3.1
4.3 MEDIUMCVSS:3.1/AV:P/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
EPSS
0.49% probability · 41th percentile
CISA KEV
Not listed
Weakness
CWE-125
Affected
yubico/libykpiv · yubico/piv tool manager · yubico/yubikey smart card minidriver
Source
cve@mitre.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.