# CVE-2018-18506: firefox: When proxy auto-detection is enabled, if a web server serves a Proxy Auto-Configuration (PAC) file or if a PAC file i...

CVE-2018-18506 is fixed in 11 products on 1 platform, first by firefox 65.0+build2-0ubuntu0.18.04.1, released January 29, 2019. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2018-18506
- Priority: Routine
- CVSS: 6.1 (Medium)
- EPSS: 0.0220
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jan 29, 2019

## Description

When proxy auto-detection is enabled, if a web server serves a Proxy Auto-Configuration (PAC) file or if a PAC file is loaded locally, this PAC file can specify that requests to the localhost are to be sent through the proxy to another server. This behavior is disallowed by default when a proxy is manually configured, but when enabled could allow for attacks on services and tools that bind to the localhost for networked behavior if they are accessed through browsing. This vulnerability affects Firefox < 65.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | firefox RHEL 8 | 0:60.6.1-1.el8 | [RHSA-2019:0966](https://patchblox.com/security/data/fix/linux/rhsa-2019-0966.md) | May 7, 2019 |
| Linux | firefox Ubuntu 18.04.6 LTS (bionic) | 65.0+build2-0ubuntu0.18.04.1 | [firefox 65.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-65.0-build2-0ubuntu0.18.04.1.md) | Jan 29, 2019 |
| Linux | firefox ol 8 | 0:60.6.1-1.0.2.el8 | [ELSA-2019-0966](https://patchblox.com/security/data/fix/linux/elsa-2019-0966.md) | Jul 30, 2019 |
| Linux | firefox-globalmenu Ubuntu 18.04.6 LTS (bionic) | 65.0+build2-0ubuntu0.18.04.1 | [firefox-globalmenu 65.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-globalmenu-65.0-build2-0ubuntu0.18.04.1.md) | Jan 29, 2019 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 65.0+build2-0ubuntu0.18.04.1 | [firefox-mozsymbols 65.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-65.0-build2-0ubuntu0.18.04.1.md) | Jan 29, 2019 |
| Linux | firefox-testsuite Ubuntu 18.04.6 LTS (bionic) | 65.0+build2-0ubuntu0.18.04.1 | [firefox-testsuite 65.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-testsuite-65.0-build2-0ubuntu0.18.04.1.md) | Jan 29, 2019 |
| Linux | thunderbird RHEL 8 | 0:60.6.1-1.el8 | [RHSA-2019:1144](https://patchblox.com/security/data/fix/linux/rhsa-2019-1144.md) | May 13, 2019 |
| Linux | thunderbird Ubuntu 18.04.6 LTS (bionic) | 1:60.6.1+build2-0ubuntu0.18.04.1 | [thunderbird 1:60.6.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-1-60.6.1-build2-0ubuntu0.18.04.1.md) | Mar 24, 2019 |
| Linux | thunderbird ol 8 | 0:60.6.1-1.0.1.el8 | [ELSA-2019-1144](https://patchblox.com/security/data/fix/linux/elsa-2019-1144.md) | Jul 30, 2019 |
| Linux | thunderbird-globalmenu Ubuntu 18.04.6 LTS (bionic) | 1:60.6.1+build2-0ubuntu0.18.04.1 | [thunderbird-globalmenu 1:60.6.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-globalmenu-1-60.6.1-build2-0ubuntu0.18.04.1.md) | Mar 24, 2019 |
| Linux | thunderbird-gnome-support Ubuntu 18.04.6 LTS (bionic) | 1:60.6.1+build2-0ubuntu0.18.04.1 | [thunderbird-gnome-support 1:60.6.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-gnome-support-1-60.6.1-build2-0ubuntu0.18.04.1.md) | Mar 24, 2019 |
| Linux | thunderbird-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 1:60.6.1+build2-0ubuntu0.18.04.1 | [thunderbird-mozsymbols 1:60.6.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-mozsymbols-1-60.6.1-build2-0ubuntu0.18.04.1.md) | Mar 24, 2019 |
| Linux | xul-ext-calendar-timezones Ubuntu 18.04.6 LTS (bionic) | 1:60.6.1+build2-0ubuntu0.18.04.1 | [xul-ext-calendar-timezones 1:60.6.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-calendar-timezones-1-60.6.1-build2-0ubuntu0.18.04.1.md) | Mar 24, 2019 |
| Linux | xul-ext-gdata-provider Ubuntu 18.04.6 LTS (bionic) | 1:60.6.1+build2-0ubuntu0.18.04.1 | [xul-ext-gdata-provider 1:60.6.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-gdata-provider-1-60.6.1-build2-0ubuntu0.18.04.1.md) | Mar 24, 2019 |
| Linux | xul-ext-lightning Ubuntu 18.04.6 LTS (bionic) | 1:60.6.1+build2-0ubuntu0.18.04.1 | [xul-ext-lightning 1:60.6.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-lightning-1-60.6.1-build2-0ubuntu0.18.04.1.md) | Mar 24, 2019 |

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