CVE-2021-42781

Program crash via unchecked Oberthur metadata lengths

Published Apr 18, 2022 · Updated Nov 3, 2025

Heap buffer overflow in OpenSC before 0.22.0 allows attackers to crash programs using the library via malformed Oberthur card data. The PKCS#15 Oberthur initialization code trusts length-prefixed label, identifier, subject, and OID fields before reading or copying beyond the metadata buffer. Triggering the flaw requires OpenSC to initialize and parse a crafted Oberthur-compatible card image; the bounded consequence is a host-process crash.

CVSS severity5.3
Medium
EPSS probability2.87%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Heap buffer overflow in OpenSC before 0.22.0 allows attackers to crash programs using the library via malformed Oberthur card data. The PKCS#15 Oberthur initialization code trusts length-prefixed label, identifier, subject, and OID fields before reading or copying beyond the metadata buffer. Triggering the flaw requires OpenSC to initialize and parse a crafted Oberthur-compatible card image; the bounded consequence is a host-process crash.

The record

CVE
CVE-2021-42781
Published
Apr 18, 2022
Updated
Nov 3, 2025
Vendor
OpenSC Project
Product
OpenSC
Classifications
CWE-119, T1499.004
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 18, 2022CVE publishedPublication date reported by the CVE source.
  2. Nov 3, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=opensc 0.22.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

OpenSC Project · OpenSCversion=opensc 0.22.0

Published CVSS scores

5.0NVDAV:N/AC:L/Au:N/C:N/I:N/A:P
7.1SUSECVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H
5.3NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
2.0Amazon LinuxCVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo