# CVE-2023-6240: Kernel: marvin vulnerability side-channel leakage in the rsa decryption operation

Status: published. Published: 2024-02-04. Updated: 2026-11-05.

A Marvin vulnerability side-channel leakage was found in the RSA decryption operation in the Linux Kernel. This issue may allow a network attacker to decrypt ciphertexts or forge signatures, limiting the services that use that private key.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 8 (kernel-rt): ≥ 0:4.18.0-553.5.1.rt7.346.el8_10; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (kernel): ≥ 0:4.18.0-553.5.1.el8_10; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (kernel): ≥ 0:5.14.0-427.16.1.el9_4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.0 Extended Update Support (kernel): ≥ 0:5.14.0-70.101.1.el9_0; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.0 Extended Update Support (kernel-rt): ≥ 0:5.14.0-70.101.1.rt21.173.el9_0; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.2 Extended Update Support (kernel): ≥ 0:5.14.0-284.62.1.el9_2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.2 Extended Update Support (kernel-rt): ≥ 0:5.14.0-284.62.1.rt14.347.el9_2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (kernel): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (kernel): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (kernel-rt): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (kernel-rt): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 6.5 (medium); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.97% as of 2026-11-04; percentile 61.96%

- SSVC: exploitation poc; 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-2024:1881 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:1882 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:2758 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:3414 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:3421 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:3618 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:3627 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2023-6240 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2250843 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://people.redhat.com/~hkario/marvin/ (CNA: redhat)

- https://securitypitfalls.wordpress.com/2023/10/16/experiment-with-side-channel-attacks-yourself/ (CNA: redhat)

- https://access.redhat.com/errata/RHSA-2024:1881 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:1882 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:2758 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:3414 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:3421 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:3618 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:3627 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/security/cve/CVE-2023-6240 (ADP: CVE; vdb-entry, x_refsource_REDHAT, x_transferred)

- https://bugzilla.redhat.com/show_bug.cgi?id=2250843 (ADP: CVE; issue-tracking, x_refsource_REDHAT, x_transferred)

- https://people.redhat.com/~hkario/marvin/ (ADP: CVE; x_transferred)

- https://securitypitfalls.wordpress.com/2023/10/16/experiment-with-side-channel-attacks-yourself/ (ADP: CVE; x_transferred)

- https://security.netapp.com/advisory/ntap-20240628-0002/ (ADP: CVE; x_transferred)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2023-6240; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2023-6240; retrieved 2026-11-05; source updated Not reported

Revision: ea206436eaca36ecc5649d79e573ec25dd863e19a212b64dc4b4a5594cecc8c9

Canonical: https://y2.dev/cve/CVE-2023-6240

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