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
Fix
Nothing published yet: no patch, vendor advisory or mitigation reference on NVD, no vendor advisory in the News for this CVE, not in CISA's KEV, no fixed package version. BaselineWatch does not guess at one.
Change history 1
- First seenCVSS 5.5 · gnomeNVD modified 2026-10-31 09:29
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 4
- https://access.redhat.com/security/cve/CVE-2026-118599 vdb-entry, x_refsource_redhat
- https://bugzilla.redhat.com/show_bug.cgi?id=2562969 issue-tracking, x_refsource_redhat
- https://gitlab.gnome.org/GNOME/epiphany/-/work_items/2988
- https://gitlab.gnome.org/GNOME/epiphany/-/merge_requests/2248