Description
Using object or embed tags, it was possible to frame other websites, even if they disallowed framing using the X-Frame-Options header. This vulnerability affects Thunderbird < 78 and Firefox < 78.0.2.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mozilla | Thunderbird | unspecified – < 78 | 78 |
| Mozilla | Firefox | unspecified – < 78.0.2 | 78.0.2 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | firefox | 79.0+build1-0ubuntu0.20.04.1 | — |
| Ubuntu 20.04 LTS | mozjs52 +1 | No fix yet | — |
| Ubuntu 20.04 LTS | thunderbird | 1:78.7.1+build1-0ubuntu0.20.04.1 | — |
| Ubuntu 18.04 LTS | firefox | 79.0+build1-0ubuntu0.18.04.1 | — |
| Ubuntu 18.04 LTS | mozjs38 +1 | No fix yet | — |
| Ubuntu 18.04 LTS | thunderbird | 1:78.8.1+build1-0ubuntu0.18.04.1 | — |
| Ubuntu 16.04 LTS | firefox | 79.0+build1-0ubuntu0.16.04.2 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | firefox | 78.2.0-2.el8_2 | RHSA-2020:3557 |
| RHEL 7 | firefox | 78.3.0-1.el7_9 | RHSA-2020:4080 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8.1 EUS | firefox | 78.2.0-3.el8_1 | RHSA-2020:3559 |
| RHEL 8.0 E4S | firefox | 78.2.0-3.el8_0 | RHSA-2020:3555 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | firefox | 78.2.0-2.0.1.el8_2 | ELSA-2020-3557 |
| Oracle Linux 7 | firefox | 78.3.0-1.0.1.el7_9 | ELSA-2020-4080 |
Advisories 7
- RHSA-2020:4080 Red Hat Security Advisory: firefox security and bug fix update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- RHSA-2020:3557 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Jan 28, 2026
- RHSA-2020:3555 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Jan 14, 2026
- RHSA-2020:3559 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Jan 14, 2026
- WID-SEC-2023-0457 Mozilla Firefox/Thunderbird: Mehrere Schwachstellen BSI CERT-Bund (WID) · May 1, 2025
- ELSA-2020-4080 Important: firefox security and bug fix update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Oct 13, 2020
- ELSA-2020-3557 Important: firefox security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Aug 28, 2020