CVE-2020-13131

4.3 MEDIUM 0.5% exploit odds Fix listed

What it is

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.

At a glance

Exploitability: Can be exploited with physical access without logging in, but needs a user to act. High risk of data exposure.
Exploit odds: 0.5% chance of exploitation in the next 30 days (EPSS).
Fix: A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

2020-07-09 18:15 UTC PublishedDisclosed publicly on CVE.org and NVD
2026-06-17 02:52 UTC Last updatedMost recent change to the record

Why it ranks here

Exploited in the wild: no, CISA does not list it.
Exploit odds: 0.5% in the next 30 days (EPSS).
Severity: 4.3 MEDIUM (CVSS).
Fix: a patch or advisory is linked.

Details

Published: 2020-07-09 18:15 UTC
Last modified: 2026-06-17 02:52 UTC
Exploit probability: 0.5% · EPSS, next 30 days
Weakness: CWE-125 · Out-of-bounds read
Record status: Modified

Affected

Yubico Libykpiv < 2.1.0
Yubico Piv Tool Manager < 2.0.0
Yubico Yubikey Smart Card Minidriver ≤ 4.1.0.172

Attack profile CVSS 3.1 · 4.3

Attack vector: Physical
Complexity: Low
Privileges needed: None
User interaction: Required
Scope: Unchanged
Confidentiality: High
Integrity: None
Availability: None

Raw vector

CVSS:3.1/AV:P/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2020-13131.md and follow it. Check whether this project is affected by CVE-2020-13131. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

· More options · Status badge

Download Square Reddit

Fix and advisories

References

NVD record · CVE.org record