Description
Sites can bypass security checks on permissions to install lightweight themes by manipulating the "baseURI" property of the theme element. This could allow a malicious site to install a theme without user interaction which could contain offensive or embarrassing images. This vulnerability affects Thunderbird < 52.8, Thunderbird ESR < 52.8, Firefox < 60, and Firefox ESR < 52.8.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mozilla | Thunderbird | unspecified – < 52.8 | 52.8 |
| Mozilla | Thunderbird ESR | unspecified – < 52.8 | 52.8 |
| Mozilla | Firefox | unspecified – < 60 | 60 |
| Mozilla | Firefox ESR | unspecified – < 52.8 | 52.8 |
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.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | firefox-esr | 52.8.0esr-1 | — |
| Debian 14 | thunderbird | 1:52.8.0-1 | — |
| Debian 13 | firefox-esr | 52.8.0esr-1 | — |
| Debian 13 | thunderbird | 1:52.8.0-1 | — |
| Debian 12 | firefox-esr | 52.8.0esr-1 | — |
| Debian 12 | thunderbird | 1:52.8.0-1 | — |
| Debian 9 | firefox-esr | 52.8.0esr-1~deb9u1 | DSA-4199-1 |
| Debian 9 | thunderbird | 1:52.8.0-1~deb9u1 | DSA-4209-1 |
| Debian 8 | firefox-esr | 52.8.0esr-1~deb8u1 | DSA-4199-1 |
| Debian 8 | thunderbird | 1:52.8.0-1~deb8u1 | DSA-4209-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 7 | firefox-esr | 52.8.0esr-1~deb7u1 | DLA-1376-1 |
| Debian 7 | thunderbird | 1:52.8.0-1~deb7u1 | DLA-1382-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | firefox | 60.0+build2-0ubuntu1 | USN-3645-1 |
| Ubuntu 18.04 LTS | thunderbird | 1:52.8.0+build1-0ubuntu0.18.04.1 | USN-3660-1 |
| Ubuntu 16.04 LTS | firefox | 60.0+build2-0ubuntu0.16.04.1 | USN-3645-1 |
| Ubuntu 16.04 LTS | thunderbird | 1:52.8.0+build1-0ubuntu0.16.04.1 | USN-3660-1 |
| Ubuntu 14.04 LTS | firefox | 60.0+build2-0ubuntu0.14.04.1 | USN-3645-1 |
| Ubuntu 14.04 LTS | thunderbird | 1:52.8.0+build1-0ubuntu0.14.04.1 | USN-3660-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | firefox +1 | 52.8.0-1.el7_5 | RHSA-2018:1725, RHSA-2018:1415 |
| RHEL 6 | firefox | 52.8.0-1.el6_9 | RHSA-2018:1414 |
| RHEL 6 | thunderbird | 52.8.0-2.el6_9 | RHSA-2018:1726 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 | MozillaFirefox | 52.9.0esr-3.7.12 | SUSE-SU-2018:2298-1 |
| SLES 12 SP5 | MozillaFirefox | 68.2.0-109.95.2 | SUSE-SU-2019:2872-1 |
| SLES 12 SP4 | MozillaFirefox | 68.2.0-109.95.2 | SUSE-SU-2019:2872-1 |
| SLES 12 SP3 | MozillaFirefox | 52.8.0esr-109.31.2 | SUSE-SU-2019:2872-1, SUSE-SU-2018:1334-1 |
| SLES 12 SP2 | MozillaFirefox | 52.8.0esr-109.31.2 | SUSE-SU-2019:2872-1, SUSE-SU-2018:1334-2, SUSE-SU-2018:1334-1 |
Show 17 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP1 | MozillaFirefox | 52.8.0esr-109.31.2 | SUSE-SU-2019:2872-1, SUSE-SU-2018:1334-1 |
| SLES 12 | MozillaFirefox | 52.8.0esr-109.31.2 | SUSE-SU-2018:1334-1 |
| SLES 11 SP4 | MozillaFirefox | 52.8.0esr-72.32.1 | SUSE-SU-2018:1319-1 |
| SLES 11 SP3 | MozillaFirefox | 52.8.0esr-72.32.1 | SUSE-SU-2018:1319-1 |
| SLES for SAP 12 SP5 | MozillaFirefox | 68.2.0-109.95.2 | SUSE-SU-2019:2872-1 |
| SLES for SAP 12 SP4 | MozillaFirefox | 68.2.0-109.95.2 | SUSE-SU-2019:2872-1 |
| SLES for SAP 12 SP3 | MozillaFirefox | 52.8.0esr-109.31.2 | SUSE-SU-2019:2872-1, SUSE-SU-2018:1334-1 |
| SLES for SAP 12 SP2 | MozillaFirefox | 52.8.0esr-109.31.2 | SUSE-SU-2019:2872-1, SUSE-SU-2018:1334-1 |
| SLES for SAP 12 SP1 | MozillaFirefox | 52.8.0esr-109.31.2 | SUSE-SU-2019:2872-1, SUSE-SU-2018:1334-1 |
| SLES for SAP 11 SP4 | MozillaFirefox | 52.8.0esr-72.32.1 | SUSE-SU-2018:1319-1 |
| SUSE OpenStack Cloud Crowbar 8 | MozillaFirefox | 68.2.0-109.95.2 | SUSE-SU-2019:2872-1 |
| SUSE OpenStack Cloud 8 | MozillaFirefox | 68.2.0-109.95.2 | SUSE-SU-2019:2872-1 |
| SUSE OpenStack Cloud 7 | MozillaFirefox | 52.8.0esr-109.31.2 | SUSE-SU-2019:2872-1, SUSE-SU-2018:1334-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | MozillaFirefox | 52.8.0esr-72.32.1 | SUSE-SU-2018:1319-1 |
| SUSE HPE Helion OpenStack 8 | MozillaFirefox | 68.2.0-109.95.2 | SUSE-SU-2019:2872-1 |
| SUSE Enterprise Storage 5 | MozillaFirefox | 68.2.0-109.95.2 | SUSE-SU-2019:2872-1 |
| SUSE Enterprise Storage 4 | MozillaFirefox | 52.8.0esr-109.31.2 | SUSE-SU-2018:1334-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | MozillaFirefox | 92.0-1.2 | openSUSE-SU-2024:10600-1 |
| openSUSE Tumbleweed | MozillaThunderbird | 91.1.1-1.1 | openSUSE-SU-2024:10601-1 |
| openSUSE Tumbleweed | firefox-esr | 128.5.1-1.1 | openSUSE-SU-2024:14572-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | thunderbird | 52.8.0-1.amzn2 | ALAS2-2018-1032 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | firefox +1 | 52.8.0-1.0.1.el7_5 | ELSA-2018-1725, ELSA-2018-1415 |
Advisories 21
- RHSA-2018:1726 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Jun 27, 2026
- RHSA-2018:1725 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Jun 27, 2026
- RHSA-2018:1415 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Jun 27, 2026
- RHSA-2018:1414 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Jun 27, 2026
- USN-3660-1 thunderbird vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- USN-3645-1 firefox vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- DSA-4199-1 firefox-esr - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-4209-1 thunderbird - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1376-1 firefox-esr - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1382-1 thunderbird - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2019:2872-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:2298-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10600-1 MozillaFirefox-92.0-1.2 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:1319-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:1334-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:1334-2 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:14572-1 firefox-esr-128.5.1-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10601-1 MozillaThunderbird-91.1.1-1.1 on GA media SUSE / openSUSE Security Updates · May 7, 2025
- ALAS2-2018-1032 Critical: thunderbird security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Jun 11, 2018
- ELSA-2018-1725 Important: thunderbird security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · May 24, 2018
- ELSA-2018-1415 Critical: firefox security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · May 14, 2018
References
- RHSA-2018:1415 vendor-advisory
- GLSA-201810-01 vendor-advisory
- RHSA-2018:1726 vendor-advisory
- RHSA-2018:1414 vendor-advisory
- GLSA-201811-13 vendor-advisory
- https://www.mozilla.org/security/advisories/mfsa2018-13/
- https://www.mozilla.org/security/advisories/mfsa2018-11/
- USN-3660-1 vendor-advisory
- 1040896 vdb-entry
- DSA-4199 vendor-advisory
- USN-3645-1 vendor-advisory
- [debian-lts-announce] 20180525 [SECURITY] [DLA 1382-1] thunderbird security update mailing-list
- [debian-lts-announce] 20180511 [SECURITY] [DLA 1376-1] firefox-esr security update mailing-list
- RHSA-2018:1725 vendor-advisory
- DSA-4209 vendor-advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1449548
- https://www.mozilla.org/security/advisories/mfsa2018-12/
- 104136 vdb-entry