{"cve":"CVE-2026-118599","nvd":{"published":"2026-10-31T10:16:38.060","modified":"2026-10-31T10:16:38.060","status":"Received","description":"A file overwrite vulnerability exists in Epiphany when installing WebExtension packages from .xpi files.\n\nIn 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.\n\nThis is related to but separate from the ZIP-slip path traversal fixed as CVE-2026-77679 (#2922 / MR !2143).\n\nRequirements: the victim must install or open a malicious WebExtension (.xpi).\n\nAffected: Epiphany >= 47.0 (WebExtension XPI install path).\nFixed: https://gitlab.gnome.org/GNOME/epiphany/-/merge_requests/2248 (commit 0cc9ab55 — only enable ZIP format support).\nUpstream: https://gitlab.gnome.org/GNOME/epiphany/-/work_items/2988\nReporter acknowledgment: Fernando Munoz","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","score":5.5},"cwes":["CWE-59"],"references":["https://access.redhat.com/security/cve/CVE-2026-118599","https://bugzilla.redhat.com/show_bug.cgi?id=2562969","https://gitlab.gnome.org/GNOME/epiphany/-/merge_requests/2248","https://gitlab.gnome.org/GNOME/epiphany/-/work_items/2988"],"products":[],"source":"nvd","synced_at":"2026-10-31T10:43:03.412806336+00:00"},"epss":null,"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}