CVE-2021-34193

Stack overflow vulnerability in OpenSC smart card middleware before 0.23 via crafted responses to APDUs.

Published: 2023-08-22 Last update: 2025-11-03 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-34193 is rated Moderate Risk (55/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.65%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-34193

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-17 0.52% 0.65% +0.13%
2 2026-02-06 0.68% 0.52% -0.16%
3 2026-02-05 — 0.68% —

Full EPSS history (15 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-34193

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2021-34193

OS Trackers for CVE-2021-34193

vendor priority summary link
alpine — CVE-2021-34193: 1 source package rows (opensc); 6 state rows across 2 repos (3.22-community, edge-community); fixed 0, open 6. https://security.alpinelinux.org/vuln/CVE-2021-34193
debian not yet assigned CVE-2021-34193 not yet assigned priority: Debian including 1 source packages (opensc), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-34193
redhat — — https://access.redhat.com/security/cve/CVE-2021-34193
suse medium CVE-2021-34193 severity moderate: SUSE including 1 source package names (opensc), 39 product×package rows across 39 product lines (SUSE CaaS Platform 4.0, SUSE Enterprise Storage 7, … (39 product lines)): Known Not Affected 39. https://www.suse.com/security/cve/CVE-2021-34193/
ubuntu medium CVE-2021-34193 medium priority: Ubuntu including 1 source packages (opensc), 10 status rows across 10 suites (bionic, focal, jammy, lunar, mantic, noble, oracular, trusty, upstream, xenial): not-affected 6, ignored 3, released 1. https://ubuntu.com/security/CVE-2021-34193

Affected software / configurations for CVE-2021-34193

Vendor Product Version Raw CPE
opensc_project opensc < 0.22.0 cpe:2.3:a:opensc_project:opensc:*:*:*:*:*:*:*:*

References for CVE-2021-34193

URL Tags
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=27719 Issue Tracking Mailing List
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=28185 Issue Tracking Mailing List
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=28383 Issue Tracking Mailing List
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=28768 Issue Tracking Mailing List
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=28843 Issue Tracking Mailing List
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=28855 Issue Tracking Mailing List
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=29912 Issue Tracking Mailing List
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=30112 Issue Tracking Mailing List
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=30800 Issue Tracking Mailing List
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=31448 Issue Tracking Mailing List
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=31540 Issue Tracking Mailing List
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=32149 Issue Tracking Mailing List
https://lists.debian.org/debian-lts-announce/2024/12/msg00026.html
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