# CVE-2026-122056: Openscap: one-byte heap buffer overflow in sds-compose may lead to denial-of-service

Status: published. Published: 2026-11-09. Updated: 2026-11-09.

A flaw was found in OpenSCAP. A heap-based buffer overflow can occur when processing a specially crafted Extensible Configuration Checklist Description Format (XCCDF) document using the sds-compose option. An attacker could exploit this vulnerability to corrupt memory, resulting in an application crash and a Denial of Service (DoS).

## Remediation

- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. (source: CNA: redhat)

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 10 (openscap): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (openscap): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (openscap): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (openscap): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (openscap): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Hardened Images (openscap): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 5.9 (medium); CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:H; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-787

## Exploit evidence

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

## References

- https://access.redhat.com/security/cve/CVE-2026-122056 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2567100 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2026-122056; retrieved 2026-11-09; source updated 2026-11-09

Revision: a3f55a99d9909a3f9ddf3f7c3bcc2b33031c72e4cb5711bcc222858bd9e1f130

Canonical: https://y2.dev/cve/CVE-2026-122056

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.