# CVE-2025-6196: Libgepub: integer overflow in libgepub's epub archive handling

Status: published. Published: 2025-06-17. Updated: 2026-11-05.

A flaw was found in libgepub, a library used to read EPUB files. The software mishandles file size calculations when opening specially crafted EPUB files, leading to incorrect memory allocations. This issue causes the application to crash. Known affected usage includes desktop services like Tumbler, which may process malicious files automatically when browsing directories. While no direct remote attack vectors are confirmed, any application using libgepub to parse user-supplied EPUB content could be vulnerable to a denial of service.

## Remediation

- workaround: Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to a widespread installation base, or stability. It is strongly recommended to apply the upstream patch once available. (source: CNA: redhat)

## Affected products and versions

-  /  (libgepub): ≥ 0; < 0.7.2 (affected, semver). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (libgepub): Version range not reported. Source: CNA: redhat

## NVD configuration conditions

Affected CPE matches depend on the following AND/OR and negation conditions:

```json
[
  {
    "negate": false,
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:gnome:libgepub:-:*:*:*:*:*:*:*",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      },
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*",
            "vulnerable": false
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ],
    "operator": "AND"
  }
]
```

## Severity and prioritization

- CVSS 3.1: 5.5 (medium); CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H; source: CNA: redhat

- CVSS 3.1: 5.5 (medium); CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H; source: NVD: secalert@redhat.com

- CISA KEV: No listing in collected sources

- EPSS: 0.24% as of 2026-11-05; percentile 14.58%

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

- Weaknesses: CWE-190

## Exploit evidence

- exploit: https://gitlab.gnome.org/GNOME/libgepub/-/issues/18 (secalert@redhat.com)

## References

- https://access.redhat.com/security/cve/CVE-2025-6196 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2373117 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://gitlab.gnome.org/GNOME/libgepub/-/issues/18 (CNA: redhat)

- https://access.redhat.com/security/cve/CVE-2025-6196 (secalert@redhat.com; Mitigation, Third Party Advisory)

- https://bugzilla.redhat.com/show_bug.cgi?id=2373117 (secalert@redhat.com; Issue Tracking, Third Party Advisory)

- https://gitlab.gnome.org/GNOME/libgepub/-/issues/18 (secalert@redhat.com; Exploit, Issue Tracking, Third Party Advisory)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2025-6196; retrieved 2026-11-05; source updated 2026-11-05

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-6196; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2025-6196; retrieved 2026-11-05; source updated Not reported

Revision: 56ada6abd414554667ae29f6a0470bb0ec340835c8800bc5b1a3e9ee1aa00b1f

Canonical: https://y2.dev/cve/CVE-2025-6196

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