Upstream information
Description
A file overwrite vulnerability exists in Epiphany when installing WebExtension packages from .xpi files.In src/webextension/ephy-web-extension-manager.c, decompress_xpi_thread() used libarchive with archive_read_support_format_all() (and filters), so the installer did not require a real ZIP. A TAR file named *.xpi was extracted. TAR supports hard-link entry types; with Epiphany's archive_write_disk options (including ARCHIVE_EXTRACT_PERM), a crafted hard-link target can cause an attacker-chosen existing user-writable file to be truncated and overwritten with attacker-controlled content and mode bits, without a dedicated warning dialog, when the user installs or opens the crafted .xpi.
This is related to but separate from the ZIP-slip path traversal fixed as CVE-2026-77679 (#2922 / MR !2143).
Requirements: the victim must install or open a malicious WebExtension (.xpi).
Affected: Epiphany >= 47.0 (WebExtension XPI install path).
Fixed: https://gitlab.gnome.org/GNOME/epiphany/-/merge_requests/2248 (commit 0cc9ab55 - only enable ZIP format support).
Upstream: https://gitlab.gnome.org/GNOME/epiphany/-/work_items/2988
Reporter acknowledgment: Fernando Munoz
SUSE information
Overall state of this security issue: Revisit
This issue is currently rated as having moderate severity.
| CVSS detail | CNA (Fedora Project) |
|---|---|
| Base Score | 5.5 |
| Vector | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N |
| Attack Vector | Local |
| Attack Complexity | Low |
| Privileges Required | None |
| User Interaction | Required |
| Scope | Unchanged |
| Confidentiality Impact | None |
| Integrity Impact | High |
| Availability Impact | None |
| CVSSv3 Version | 3.1 |
SUSE Timeline for this CVE
CVE page created: Fri Oct 30 15:56:02 2026CVE page last modified: Sat Oct 31 13:56:48 2026