# CVE-2026-103242: Rpm: heap-based buffer overflow write in hex2binv() via a mistyped rpmtag_filesignatures header tag

Status: published. Published: 2026-09-30. Updated: 2026-11-05.

A heap-based buffer overflow flaw was found in rpm. RPMTAG_FILESIGNATURES in a crafted, unsigned RPM package's main header is declared with the wrong header type, causing hex2binv() to allocate a one-byte buffer and then write the tag's attacker-controlled, hex-decoded content — of attacker-chosen length — past the end of that allocation. This is reachable via rpm2cpio, rpm2archive, and rpm -qlvp on an untrusted package.

## Remediation

- workaround: Avoid processing or extracting RPM packages from untrusted or unsigned sources. Do not run rpm -qlvp, rpm2cpio, or rpm2archive against RPM files whose origin and integrity cannot be verified. (source: CNA: redhat)

## Affected products and versions

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

## Severity and prioritization

- CVSS 3.1: 7.1 (high); CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H; source: CNA: redhat

- CVSS 3.1: 7.1 (high); CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H; source: NVD: secalert@redhat.com

- CISA KEV: No listing in collected sources

- EPSS: 0.12% as of 2026-11-05; percentile 1.80%

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

- Weaknesses: CWE-122

## Exploit evidence

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

## References

- https://access.redhat.com/security/cve/CVE-2026-103242 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2543866 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2026-103242 (secalert@redhat.com)

- https://bugzilla.redhat.com/show_bug.cgi?id=2543866 (secalert@redhat.com)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2026-103242; retrieved 2026-11-05; source updated 2026-11-05

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-103242; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-103242; retrieved 2026-11-05; source updated Not reported

Revision: d6cfcc2bc987ff63d5b28bfe8e2c27f16dca7fc36328cd6734c80884e91ee805

Canonical: https://y2.dev/cve/CVE-2026-103242

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