CVE-2026-115683
epiphany: TLS certificate warning bypass via race in tlsErrorPage message handler
A race condition in Epiphany allows a malicious website to bypass the TLS/SSL certificate warning page.
Epiphany 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.
If 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.
Upstream report: https://gitlab.gnome.org/GNOME/epiphany/-/work_items/2978 Proof of concept: https://beford.net/poc/ssl_poc.html Fix: 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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
6.8
epiphany: TLS certificate warning bypass via race in tlsErrorPage message handler
A race condition in Epiphany allows a malicious website to bypass the TLS/SSL certificate warning page.
Epiphany 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.
If 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.
Upstream report: https://gitlab.gnome.org/GNOME/epiphany/-/work_items/2978 Proof of concept: https://beford.net/poc/ssl_poc.html Fix: 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.
- Record
CVE-2026-115683- CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N - Weakness
- CWE-367
- Updated
- 2026-11-02
EUVDEUVD-2026-113941
6.8
A race condition in Epiphany allows a malicious website to bypass the TLS/SSL certificate warning page.
Epiphany 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.
If 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.
Upstream report: https://gitlab.gnome.org/GNOME/epiphany/-/work_items/2978 Proof of concept: https://beford.net/poc/ssl_poc.html Fix: 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.
- Record
EUVD-2026-113941- CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-rgq4-6fxx-v9rg
6.8
A race condition in Epiphany allows a malicious website to bypass the TLS/SSL certificate warning...
A race condition in Epiphany allows a malicious website to bypass the TLS/SSL certificate warning page.
Epiphany 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.
If 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.
Upstream report: https://gitlab.gnome.org/GNOME/epiphany/-/work_items/2978 Proof of concept: https://beford.net/poc/ssl_poc.html Fix: 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.
- Record
GHSA-rgq4-6fxx-v9rg- CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N - Weakness
- CWE-367
- Updated
- 2026-11-02
NVD
6.8
A race condition in Epiphany allows a malicious website to bypass the TLS/SSL certificate warning page.
Epiphany 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.
If 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.
Upstream report: https://gitlab.gnome.org/GNOME/epiphany/-/work_items/2978 Proof of concept: https://beford.net/poc/ssl_poc.html Fix: 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.
- Record
CVE-2026-115683- CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N - Weakness
- CWE-367
- Updated
- 2026-11-02
OSV
6.8
epiphany: TLS certificate warning bypass via race in tlsErrorPage message handler
A race condition in Epiphany allows a malicious website to bypass the TLS/SSL certificate warning page.
Epiphany 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.
If 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.
Upstream report: https://gitlab.gnome.org/GNOME/epiphany/-/work_items/2978 Proof of concept: https://beford.net/poc/ssl_poc.html Fix: 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.
- Record
CVE-2026-115683- CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N - Weakness
- CWE-367
- Updated
- 2026-11-04
OSVDEBIAN-CVE-2026-115683
6.8
A race condition in Epiphany allows a malicious website to bypass the TLS/SSL certificate warning page. Epiphany 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. If 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. Upstream report: https://gitlab.gnome.org/GNOME/epiphany/-/work_items/2978 Proof of concept: https://beford.net/poc/ssl_poc.html Fix: 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.
- Record
DEBIAN-CVE-2026-115683- CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N - Updated
- 2026-11-04
OSVUBUNTU-CVE-2026-115683
6.8
A race condition in Epiphany allows a malicious website to bypass the TLS/SSL certificate warning page. Epiphany 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. If 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. Upstream report: https://gitlab.gnome.org/GNOME/epiphany/-/work_items/2978 Proof of concept: https://beford.net/poc/ssl_poc.html Fix: 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.
- Record
UBUNTU-CVE-2026-115683- CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N - Updated
- 2026-11-05
OSVopenSUSE-SU-2026:12379-1 No score
epiphany-51.2-1.1 on GA media
These are all security issues fixed in the epiphany-51.2-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2026:12379-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
epiphany-browserDebian:12 |
All versions, plus listed versions 43.1-144.0-144.1-144.2-144.3-1 Show 43 moreShow less44.5-144.5-244.6-144~rc-145.0-145.1-145.2-145~beta-146.0-146.0-246.1-146.2-146.3-146~alpha-146~beta-147.0-147.2-147~beta-147~rc-148.0-148.1-148.2-148.3-148.3-248.5-148.5-248.5-348~beta-148~rc-148~rc-249.0-149.1-149.2-149.2-249.2-350.3-150.3-250.4-150.4-251.0-151.1-151.2-151~rc-1 |
None known |
epiphany-browserDebian:13 |
All versions, plus listed versions 48.3-248.5-0+deb13u148.5-148.5-248.5-3 Show 13 moreShow less49.0-149.1-149.2-149.2-249.2-350.3-150.3-250.4-150.4-251.0-151.1-151.2-151~rc-1 |
None known |
epiphany-browserDebian:14 |
before 51.2-1, plus listed versions 48.3-248.5-148.5-248.5-349.0-1 Show 11 moreShow less49.1-149.2-149.2-249.2-350.3-150.3-250.4-150.4-251.0-151.1-151~rc-1 |
51.2-1 |
epiphany-browserUbuntu:16.04:LTS |
All versions, plus listed versions 3.16.3-1ubuntu13.18.0-1ubuntu23.18.1-1ubuntu13.18.3-0ubuntu13.18.5-0ubuntu13.18.5-0ubuntu1.13.18.10-0ubuntu13.18.11-0ubuntu1 |
None known |
epiphany-browserUbuntu:18.04:LTS |
All versions, plus listed versions 3.26.1-1ubuntu13.26.1-1ubuntu23.26.1-1ubuntu43.26.5.1-1ubuntu13.27.90-1ubuntu1 Show 4 moreShow less3.28.0.1-1ubuntu13.28.1-1ubuntu13.28.5-0ubuntu13.28.6-0ubuntu1 |
None known |
epiphany-browserUbuntu:20.04:LTS |
All versions, plus listed versions 3.34.1-13.34.1-1build13.36.0-13.36.1-13.36.2-0ubuntu13.36.3-0ubuntu13.36.4-0ubuntu13.36.4-0ubuntu2 |
None known |
epiphany-browserUbuntu:22.04:LTS |
All versions, plus listed versions 41.0-141.0-241.2-141.3-142~beta-1 Show 4 moreShow less42.0-142.1-142.1-1ubuntu142.4-0ubuntu1 |
None known |
epiphany-browserUbuntu:24.04:LTS |
All versions, plus listed versions 45.0-145.1-146~alpha-146~beta-146.0-146.0-2build146.5-0ubuntu1 |
None known |
epiphany-browserUbuntu:26.10 |
All versions, plus listed versions 49.2-3ubuntu150.4-150.4-2 |
None known |
epiphany-browserUbuntu:26.04:LTS |
All versions, plus listed versions 48.5-349.1-149.2-149.2-249.2-349.2-3ubuntu1 |
None known |
epiphanyopenSUSE:Tumbleweed From an advisory covering 3 CVEs |
before 51.2-1.1 | 51.2-1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected | ||
| published | OSV | |
| affected | OSV | |
| facts | OSV | |
| affected | OSV | |
| references | OSV | |
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-115683 is a medium vulnerability (CVSS 6.8) in Gnome Epiphany, published October 30, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.22%, the 12th percentile. Fixed in epiphany-browser 51.2-1.
References
access.redhat.com/security/cve/CVE-2026-115683
bugzilla.redhat.com/show_bug.cgi?id=2560012
gitlab.gnome.org/GNOME/epiphany/-/work_items/2978
gitlab.gnome.org/GNOME/epiphany/-/merge_requests/2245
beford.net/poc/ssl_poc.html
nvd.nist.gov/vuln/detail/CVE-2026-115683
Show 9 moreShow less
github.com/advisories/GHSA-rgq4-6fxx-v9rg
github.com/CVEProject/cvelistV5/tree/main/cves/2026/115xxx/CVE-2026-115683.json
gitlab.gnome.org/GNOME/epiphany
security-tracker.debian.org/tracker/CVE-2026-115683
ubuntu.com/security/CVE-2026-115683
cve.org/CVERecord?id=CVE-2026-115683
suse.com/security/cve/CVE-2026-115683
suse.com/security/cve/CVE-2026-118598
suse.com/security/cve/CVE-2026-118599