Description
The Mozilla Maintenance Service "helper.exe" application creates a temporary directory writable by non-privileged users. When this is combined with creation of a junction (a form of symbolic link), protected files in the target directory of the junction can be deleted by the Mozilla Maintenance Service, which has privileged access. Note: This attack requires local system access and only affects Windows. Other operating systems are not affected. This vulnerability affects Firefox ESR < 52.2 and Firefox < 54.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mozilla | Firefox ESR | unspecified – < 52.2 | 52.2 |
| Mozilla | Firefox | unspecified – < 54 | 54 |
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.
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP2 | MozillaFirefox | 52.2.0esr-108.3 | SUSE-SU-2017:1669-1 |
| SLES 12 SP2 | MozillaFirefox-branding-SLE | 52-31.1 | SUSE-SU-2017:1669-1 |
| SLES 12 SP1 | MozillaFirefox | 52.2.0esr-108.3 | SUSE-SU-2017:1669-1 |
| SLES 12 SP1 | MozillaFirefox-branding-SLE | 52-31.1 | SUSE-SU-2017:1669-1 |
| SLES 12 | MozillaFirefox | 52.2.0esr-108.3 | SUSE-SU-2017:1669-1 |
| SLES 12 | MozillaFirefox-branding-SLE | 52-31.1 | SUSE-SU-2017:1669-1 |
| SLES 11 SP4 | MozillaFirefox | 52.2.0esr-72.5.2 | SUSE-SU-2017:2235-1 |
| SLES 11 SP4 | MozillaFirefox-branding-SLED | 52-24.3.44 | SUSE-SU-2017:2235-1 |
| SLES 11 SP4 | firefox-gcc5 +1 | 5.3.1+r233831-7.1 | SUSE-SU-2017:2235-1 |
| SLES 11 SP4 | mozilla-nss | 3.29.5-47.3.2 | SUSE-SU-2017:2235-1 |
| SLES 11 SP3 | MozillaFirefox | 52.2.0esr-72.5.2 | SUSE-SU-2017:2235-1 |
| SLES 11 SP3 | MozillaFirefox-branding-SLED | 52-24.3.44 | SUSE-SU-2017:2235-1 |
| SLES 11 SP3 | firefox-gcc5 +1 | 5.3.1+r233831-7.1 | SUSE-SU-2017:2235-1 |
| SLES 11 SP3 | mozilla-nss | 3.29.5-47.3.2 | SUSE-SU-2017:2235-1 |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP2 | MozillaFirefox | 52.2.0esr-108.3 | SUSE-SU-2017:1669-1 |
| SLES for SAP 12 SP2 | MozillaFirefox-branding-SLE | 52-31.1 | SUSE-SU-2017:1669-1 |
| SLES for SAP 12 SP1 | MozillaFirefox | 52.2.0esr-108.3 | SUSE-SU-2017:1669-1 |
| SLES for SAP 12 SP1 | MozillaFirefox-branding-SLE | 52-31.1 | SUSE-SU-2017:1669-1 |
| SLES for SAP 12 | MozillaFirefox | 52.2.0esr-108.3 | SUSE-SU-2017:1669-1 |
| SLES for SAP 12 | MozillaFirefox-branding-SLE | 52-31.1 | SUSE-SU-2017:1669-1 |
| SLES for SAP 11 SP4 | MozillaFirefox | 52.2.0esr-72.5.2 | SUSE-SU-2017:2235-1 |
| SLES for SAP 11 SP4 | MozillaFirefox-branding-SLED | 52-24.3.44 | SUSE-SU-2017:2235-1 |
| SLES for SAP 11 SP4 | firefox-gcc5 +1 | 5.3.1+r233831-7.1 | SUSE-SU-2017:2235-1 |
| SLES for SAP 11 SP4 | mozilla-nss | 3.29.5-47.3.2 | SUSE-SU-2017:2235-1 |
| SUSE OpenStack Cloud 6 | MozillaFirefox | 52.2.0esr-108.3 | SUSE-SU-2017:1669-1 |
| SUSE OpenStack Cloud 6 | MozillaFirefox-branding-SLE | 52-31.1 | SUSE-SU-2017:1669-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | MozillaFirefox | 52.2.0esr-72.5.2 | SUSE-SU-2017:2235-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | MozillaFirefox-branding-SLED | 52-24.3.44 | SUSE-SU-2017:2235-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | firefox-gcc5 +1 | 5.3.1+r233831-7.1 | SUSE-SU-2017:2235-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | mozilla-nss | 3.29.5-47.3.2 | SUSE-SU-2017:2235-1 |
Advisories 2
- SUSE-SU-2017:2235-1 Security update for MozillaFirefox, MozillaFirefox-branding-SLED, firefox-gcc5, mozilla-nss SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:1669-1 Security update for MozillaFirefox, MozillaFirefox-branding-SLE SUSE / openSUSE Security Updates · Feb 4, 2026