{"id":"CVE-2026-115683","kind":"vulnerability","aliases":["CVE-2026-115683"],"related":[],"title":"Epiphany browser: race lets a malicious site skip certificate warnings","description":"A race condition in Epiphany allows a malicious website to bypass the TLS/SSL certificate warning page.\n\nEpiphany registers the main-world script message handler \"tlsErrorPage\" so its internal TLS error page can implement \"Accept Risk and Proceed\". The handler was registered immediately before loading the error page, leaving a brief window where the previously loaded untrusted origin could still call window.webkit.messageHandlers.tlsErrorPage.postMessage(...). The only authorization check compares a numeric WebKit page id that increments predictably; an attacker can burst-guess ids and approve a certificate exception with no user click.\n\nIf a victim visits malicious site A that redirects to site B with an invalid certificate, site A can, for a few milliseconds, disable TLS certificate error warnings for host B until Epiphany is restarted, enabling man-in-the-middle or site spoofing for that host.\n\nUpstream report: https://gitlab.gnome.org/GNOME/epiphany/-/work_items/2978\nProof of concept: https://beford.net/poc/ssl_poc.html\nFix: https://gitlab.gnome.org/GNOME/epiphany/-/merge_requests/2245 (register handlers on LOAD_COMMITTED). No fixed release tagged yet; reporter and maintainer describe all current versions as affected. Maintainer notes the risky registration timing dates to commit 1da1caed (Epiphany 45.x era); before that the handlers were always registered and similarly reachable from web content.","summary":"Epiphany, the GNOME web browser, has a race condition that lets a malicious page approve a certificate exception for another host without a user click. An attacker who gets a victim to a malicious site can then perform man-in-the-middle attacks or spoof the target site until Epiphany restarts.","severity":"medium","cvss":6.8,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["epiphany","gnome","linux-desktop","package"],"not_affected_if":["other-browser"],"how_to_check":"- Check the installed Epiphany version with `epiphany --version`, since the sources say all current versions are affected.\n- Confirm whether the browser is in use on the machine (flatpak or distro package).","fix":"- Fixed release: unknown; the sources say no fixed release is tagged yet.\n- Upstream fix exists as a merge request that registers handlers on LOAD_COMMITTED, but no released version is stated.","status":"open","published_at":"2026-10-30T14:16:39+00:00","first_seen_at":"2026-10-30T14:30:53+00:00","triaged_at":"2026-10-30T14:32:50+00:00","updated_at":"2026-10-30T14:32:50+00:00","category":"package","confidence":0.7,"triage":{"at":"2026-10-30T14:32:50Z","model":"claude-haiku-5-5","output":{"fix":"- Fixed release: unknown; the sources say no fixed release is tagged yet.\n- Upstream fix exists as a merge request that registers handlers on LOAD_COMMITTED, but no released version is stated.","reach":"internet","title":"Epiphany browser: race lets a malicious site skip certificate warnings","impact":"medium","summary":"Epiphany, the GNOME web browser, has a race condition that lets a malicious page approve a certificate exception for another host without a user click. An attacker who gets a victim to a malicious site can then perform man-in-the-middle attacks or spoof the target site until Epiphany restarts.","audience":"everyone","category":"package","nicknames":[],"who_cares":["epiphany","gnome","linux-desktop"],"confidence":0.7,"fix_status":"none","needs_auth":"no","worst_case":"Attacker bypasses certificate warnings and intercepts traffic to another host.","analyst_note":"Confirm the fixed release version once GNOME tags it, via the MR at https://gitlab.gnome.org/GNOME/epiphany/-/merge_requests/2245.","how_to_check":"- Check the installed Epiphany version with `epiphany --version`, since the sources say all current versions are affected.\n- Confirm whether the browser is in use on the machine (flatpak or distro package).","plain_action":"Epiphany has no released fix yet, so avoid relying on its certificate warnings and wait for an update from the GNOME project.","needs_analyst":true,"not_affected_if":["other-browser"],"who_is_affected":"Anyone using Epiphany (GNOME Web) as a browser; the sources say all current versions are affected and the timing issue dates to the Epiphany 45.x era. The flaw is in the browser's own error page logic, so it applies to users browsing the web with Epiphany rather than to servers. Systems not running Epiphany can skip it.","user_interaction":"yes","needs_special_setup":"no","severity_if_unknown":"medium"},"cost_usd":0.000795,"input_tokens":4525,"output_tokens":686,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-115683':13A,16A '-2026':12A,15A '/gnome/epiphany/-/merge_requests/2245':227C '/gnome/epiphany/-/work_items/2978':217C '/poc/ssl_poc.html':223C '1da1caed':256C '45':258C 'accept':109C 'affect':246C 'allow':80C 'alway':266C 'anoth':42B 'approv':37B,158C 'attack':49B,66B,151C 'author':139C 'b':177C,196C 'beford.net':222C 'beford.net/poc/ssl_poc.html':221C 'brief':125C 'browser':2A,27B 'burst':154C 'burst-guess':153C 'bypass':85C 'call':135C 'certif':9A,39B,88C,160C,181C,191C 'check':140C 'click':47B,165C 'commit':232C,255C 'compar':141C 'concept':220C 'condit':31B,77C 'content':273C 'could':133C 'current':243C 'cve':11A,14A 'date':253C 'describ':241C 'desktop':21B 'disabl':189C 'enabl':201C 'epiphani':1A,17B,23B,73B,79C,91C,198C,257C 'era':260C 'error':105C,121C,192C 'except':40B,161C 'fix':224C,234C 'get':51B 'gitlab.gnome.org':216C,226C 'gitlab.gnome.org/gnome/epiphany/-/merge_requests/2245':225C 'gitlab.gnome.org/gnome/epiphany/-/work_items/2978':215C 'gnome':18B,25B 'guess':155C 'handler':99C,114C,229C,264C 'host':43B,195C,212C 'id':146C,156C 'immedi':117C 'implement':108C 'increment':148C 'intern':103C 'invalid':180C 'leav':123C 'let':4A,33B 'linux':20B 'linux-desktop':19B 'load':119C,130C,231C 'main':95C 'main-world':94C 'maintain':240C,247C 'malici':6A,35B,56B,82C,170C 'man':62B,203C 'man-in-the-middl':61B,202C 'messag':98C 'middl':65B,206C 'millisecond':188C 'note':248C 'numer':143C 'origin':132C 'packag':22B 'page':36B,90C,106C,122C,145C 'perform':60B 'predict':149C 'previous':129C 'proceed':112C 'proof':218C 'race':3A,30B,76C 'reachabl':270C 'redirect':174C 'regist':92C,116C,228C,267C 'registr':251C 'releas':235C 'report':214C,238C 'restart':74B,200C 'risk':110C 'riski':250C 'script':97C 'similar':269C 'site':7A,57B,71B,171C,176C,182C,208C 'skip':8A 'spoof':68B,209C 'still':134C 'tag':236C 'target':70B 'time':252C 'tls':104C,190C 'tls/ssl':87C 'tlserrorpag':100C 'untrust':131C 'upstream':213C 'user':46B,164C 'version':244C 'victim':53B,168C 'visit':169C 'warn':10A,89C,193C 'web':26B,272C 'webkit':144C 'websit':83C 'window':126C 'window.webkit.messagehandlers.tlserrorpage.postmessage':136C 'without':44B 'world':96C 'x':259C 'yet':237C","nicknames":[],"mitigations":[],"who_affected":"Anyone using Epiphany (GNOME Web) as a browser; the sources say all current versions are affected and the timing issue dates to the Epiphany 45.x era. The flaw is in the browser's own error page logic, so it applies to users browsing the web with Epiphany rather than to servers. Systems not running Epiphany can skip it.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"none","audience":"everyone","plain_action":"Epiphany has no released fix yet, so avoid relying on its certificate warnings and wait for an update from the GNOME project.","first_public_at":"2026-10-30T14:16:39+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N","cvss_by":"patrick@puiterwijk.org","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-115683","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-115683","severity":null,"published_at":"2026-10-30T14:16:39+00:00","modified_at":"2026-10-30T14:16:39+00:00","first_seen_at":"2026-10-30T14:30:53+00:00","fetched_at":"2026-10-30T14:30:53+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}