# CVE-2023-5992: Opensc: side-channel leaks while stripping encryption pkcs#1 padding

Status: published. Published: 2024-01-31. Updated: 2026-11-05.

A vulnerability was found in OpenSC where PKCS#1 encryption padding removal is not implemented as side-channel resistant. This issue may result in the potential leak of private data.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 8 (opensc): ≥ 0:0.20.0-8.el8_9; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (opensc): ≥ 0:0.23.0-4.el9_3; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (opensc): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 5.6 (medium); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 1.16% as of 2026-11-04; percentile 67.14%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-203

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://access.redhat.com/errata/RHSA-2024:0966 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:0967 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2023-5992 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2248685 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://github.com/OpenSC/OpenSC/wiki/CVE-2023-5992 (CNA: redhat)

- https://www.usenix.org/system/files/usenixsecurity24-shagam.pdf (CNA: redhat)

- https://access.redhat.com/errata/RHSA-2024:0966 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:0967 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/security/cve/CVE-2023-5992 (ADP: CVE; vdb-entry, x_refsource_REDHAT, x_transferred)

- https://bugzilla.redhat.com/show_bug.cgi?id=2248685 (ADP: CVE; issue-tracking, x_refsource_REDHAT, x_transferred)

- https://github.com/OpenSC/OpenSC/wiki/CVE-2023-5992 (ADP: CVE; x_transferred)

- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/OWIZ5ZLO5ECYPLSTESCF7I7PQO5X6ZSU/ (ADP: CVE; x_transferred)

- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/RJI2FWLY24EOPALQ43YPQEZMEP3APPPI/ (ADP: CVE; x_transferred)

- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UECKC7X4IM4YZQ5KRQMNBNKNOXLZC7RZ/ (ADP: CVE; x_transferred)

- https://lists.debian.org/debian-lts-announce/2024/12/msg00026.html (ADP: CVE)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2023-5992; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2023-5992; retrieved 2026-11-05; source updated Not reported

Revision: 5159bbe5af34aedb50416252fcd00f1e4d4d87c60a46358e8e1c83158b5fbb7a

Canonical: https://y2.dev/cve/CVE-2023-5992

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