CVE-2020-12390
Incorrect origin serialization of URLs with IPv6 addresses could lead to incorrect security...
9.8 CriticalFix available
Incorrect origin serialization of URLs with IPv6 addresses could lead to incorrect security checks. This vulnerability affects Firefox < 76.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
1.62%Up 1.0 points since Apr 14, 2021
What each source reports
NVD Score used
Incorrect origin serialization of URLs with IPv6 addresses could lead to incorrect security checks. This vulnerability affects Firefox < 76.
- Record
CVE-2020-12390- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-502
- Updated
- 2026-11-02
CVE List No score
Incorrect origin serialization of URLs with IPv6 addresses could lead to incorrect security checks. This vulnerability affects Firefox < 76.
- Record
CVE-2020-12390- Updated
- 2026-11-02
EUVDEUVD-2020-4702 No score
Incorrect origin serialization of URLs with IPv6 addresses could lead to incorrect security checks. This vulnerability affects Firefox < 76.
- Record
EUVD-2020-4702- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-2hhq-96pp-rf56 No score
Incorrect origin serialization of URLs with IPv6 addresses could lead to incorrect security...
Incorrect origin serialization of URLs with IPv6 addresses could lead to incorrect security checks. This vulnerability affects Firefox < 76.
- Record
GHSA-2hhq-96pp-rf56- Updated
- 2026-11-02
OSVALPINE-CVE-2020-12390
Incorrect origin serialization of URLs with IPv6 addresses could lead to incorrect security checks. This vulnerability affects Firefox < 76.
- Record
ALPINE-CVE-2020-12390- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-03
OSVRHSA-2020:3557
Red Hat Security Advisory: firefox security update
- Record
RHSA-2020:3557- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Show 4 moreShow less
OSVUBUNTU-CVE-2020-12390
Incorrect origin serialization of URLs with IPv6 addresses could lead to incorrect security checks. This vulnerability affects Firefox < 76.
- Record
UBUNTU-CVE-2020-12390- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVopenSUSE-SU-2024:10600-1 No score
MozillaFirefox-92.0-1.2 on GA media
These are all security issues fixed in the MozillaFirefox-92.0-1.2 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2024:10600-1- Updated
- 2026-11-02
OSVopenSUSE-SU-2024:14572-1 No score
firefox-esr-128.5.1-1.1 on GA media
These are all security issues fixed in the firefox-esr-128.5.1-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2024:14572-1- Updated
- 2026-11-02
OSVUSN-4353-1 No score
firefox vulnerabilities
Multiple security issues were discovered in Firefox. If a user were tricked in to opening a specially crafted website, an attacker could potentially exploit these to cause a denial of service, bypass security restrictions, spoof the URL bar, or execute arbitrary code. (CVE-2020-6831, CVE-2020-12387, CVE-2020-12390, CVE-2020-12391, CVE-2020-12394, CVE-2020-12395, CVE-2020-12396)
It was discovered that the Devtools’ ‘Copy as cURL’ feature did not properly escape the HTTP POST data of a request. If a user were tricked in to using the ‘Copy as cURL’ feature to copy and paste a command with specially crafted data in to a terminal, an attacker could potentially exploit this to obtain sensitive information from local files. (CVE-2020-12392)
- Record
USN-4353-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
firefoxAlpine:v3.12 |
before 76.0-r0 | 76.0-r0 |
firefoxAlpine:v3.13 |
before 76.0-r0 | 76.0-r0 |
firefoxAlpine:v3.14 |
before 76.0-r0 | 76.0-r0 |
firefoxAlpine:v3.15 |
before 76.0-r0 | 76.0-r0 |
firefoxAlpine:v3.16 |
before 76.0-r0 | 76.0-r0 |
firefoxAlpine:v3.17 |
before 76.0-r0 | 76.0-r0 |
firefoxAlpine:v3.18 |
before 76.0-r0 | 76.0-r0 |
firefoxAlpine:v3.19 |
before 76.0-r0 | 76.0-r0 |
firefoxAlpine:v3.20 |
before 76.0-r0 | 76.0-r0 |
firefoxAlpine:v3.21 |
before 76.0-r0 | 76.0-r0 |
Show 21 moreShow less
| Package | Affected | Fixed |
|---|---|---|
firefoxAlpine:v3.22 |
before 76.0-r0 | 76.0-r0 |
firefoxAlpine:v3.23 |
before 76.0-r0 | 76.0-r0 |
librewolfAlpine:v3.21 |
before 76.0-r0 | 76.0-r0 |
librewolfAlpine:v3.22 |
before 76.0-r0 | 76.0-r0 |
librewolfAlpine:v3.23 |
before 76.0-r0 | 76.0-r0 |
librewolfAlpine:v3.24 |
before 76.0-r0 | 76.0-r0 |
firefoxRed Hat:enterprise_linux:8::appstream From an advisory covering 11 CVEs |
before 0:78.2.0-2.el8_2 | 0:78.2.0-2.el8_2 |
firefox-debuginfoRed Hat:enterprise_linux:8::appstream From an advisory covering 11 CVEs |
before 0:78.2.0-2.el8_2 | 0:78.2.0-2.el8_2 |
firefox-debugsourceRed Hat:enterprise_linux:8::appstream From an advisory covering 11 CVEs |
before 0:78.2.0-2.el8_2 | 0:78.2.0-2.el8_2 |
firefoxUbuntu:16.04:LTS |
before 76.0+build2-0ubuntu0.16.04.1, plus listed versions 41.0.2+build2-0ubuntu142.0+build2-0ubuntu144.0+build3-0ubuntu244.0.1+build1-0ubuntu144.0.2+build1-0ubuntu1 Show 45 moreShow less45.0+build2-0ubuntu145.0.1+build1-0ubuntu145.0.2+build1-0ubuntu146.0+build5-0ubuntu0.16.04.246.0.1+build1-0ubuntu0.16.04.247.0+build3-0ubuntu0.16.04.148.0+build2-0ubuntu0.16.04.149.0+build4-0ubuntu0.16.04.149.0.2+build2-0ubuntu0.16.04.250.0+build2-0ubuntu0.16.04.250.0.2+build1-0ubuntu0.16.04.150.1.0+build2-0ubuntu0.16.04.151.0.1+build2-0ubuntu0.16.04.151.0.1+build2-0ubuntu0.16.04.252.0+build2-0ubuntu0.16.04.152.0.1+build2-0ubuntu0.16.04.152.0.2+build1-0ubuntu0.16.04.153.0+build6-0ubuntu0.16.04.153.0.2+build1-0ubuntu0.16.04.253.0.3+build1-0ubuntu0.16.04.254.0+build3-0ubuntu0.16.04.155.0.1+build2-0ubuntu0.16.04.255.0.2+build1-0ubuntu0.16.04.156.0+build6-0ubuntu0.16.04.156.0+build6-0ubuntu0.16.04.257.0+build4-0ubuntu0.16.04.557.0+build4-0ubuntu0.16.04.657.0.1+build2-0ubuntu0.16.04.157.0.3+build1-0ubuntu0.16.04.157.0.4+build1-0ubuntu0.16.04.158.0+build6-0ubuntu0.16.04.158.0.1+build1-0ubuntu0.16.04.158.0.2+build1-0ubuntu0.16.04.159.0+build5-0ubuntu0.16.04.159.0.1+build1-0ubuntu0.16.04.159.0.2+build1-0ubuntu0.16.04.159.0.2+build1-0ubuntu0.16.04.360.0+build2-0ubuntu0.16.04.160.0.1+build2-0ubuntu0.16.04.160.0.2+build1-0ubuntu0.16.04.161.0+build3-0ubuntu0.16.04.261.0.1+build1-0ubuntu0.16.04.162.0+build2-0ubuntu0.16.04.362.0+build2-0ubuntu0.16.04.462.0+build2-0ubuntu0.16.04.5 |
76.0+build2-0ubuntu0.16.04.1 |
firefoxUbuntu:18.04:LTS |
before 76.0+build2-0ubuntu0.18.04.1, plus listed versions 56.0+build6-0ubuntu157.0.1+build2-0ubuntu159.0.1+build1-0ubuntu159.0.2+build1-0ubuntu160.0+build2-0ubuntu1 Show 40 moreShow less60.0.1+build2-0ubuntu0.18.04.160.0.2+build1-0ubuntu0.18.04.161.0+build3-0ubuntu0.18.04.161.0.1+build1-0ubuntu0.18.04.162.0+build2-0ubuntu0.18.04.362.0+build2-0ubuntu0.18.04.462.0+build2-0ubuntu0.18.04.562.0.3+build1-0ubuntu0.18.04.163.0+build2-0ubuntu0.18.04.263.0.3+build1-0ubuntu0.18.04.164.0+build3-0ubuntu0.18.04.165.0+build2-0ubuntu0.18.04.165.0.1+build2-0ubuntu0.18.04.166.0+build3-0ubuntu0.18.04.166.0.1+build1-0ubuntu0.18.04.166.0.2+build1-0ubuntu0.18.04.166.0.3+build1-0ubuntu0.18.04.166.0.4+build3-0ubuntu0.18.04.166.0.5+build1-0ubuntu0.18.04.167.0+build2-0ubuntu0.18.04.167.0.1+build1-0ubuntu0.18.04.167.0.2+build2-0ubuntu0.18.04.167.0.3+build1-0ubuntu0.18.04.167.0.4+build1-0ubuntu0.18.04.168.0+build3-0ubuntu0.18.04.168.0.1+build1-0ubuntu0.18.04.168.0.2+build1-0ubuntu0.18.04.169.0+build2-0ubuntu0.18.04.169.0.1+build1-0ubuntu0.18.04.169.0.2+build1-0ubuntu0.18.04.170.0+build2-0ubuntu0.18.04.170.0.1+build1-0ubuntu0.18.04.171.0+build5-0ubuntu0.18.04.172.0.1+build1-0ubuntu0.18.04.172.0.2+build1-0ubuntu0.18.04.173.0+build3-0ubuntu0.18.04.173.0.1+build1-0ubuntu0.18.04.174.0+build3-0ubuntu0.18.04.174.0.1+build1-0ubuntu0.18.04.175.0+build3-0ubuntu0.18.04.1 |
76.0+build2-0ubuntu0.18.04.1 |
mozjs52Ubuntu:18.04:LTS |
All versions, plus listed versions 52.3.1-0ubuntu352.3.1-7fakesync152.8.1-0ubuntu0.18.04.152.9.1-0ubuntu0.18.04.1 |
None known |
mozjs38Ubuntu:18.04:LTS |
All versions, plus listed versions 38.8.0~repack1-0ubuntu138.8.0~repack1-0ubuntu338.8.0~repack1-0ubuntu4 |
None known |
firefoxUbuntu:20.04:LTS |
before 76.0+build2-0ubuntu0.20.04.1, plus listed versions 69.0.3+build1-0ubuntu170.0+build2-0ubuntu170.0+build2-0ubuntu270.0.1+build1-0ubuntu271.0+build2-0ubuntu2 Show 12 moreShow less71.0+build5-0ubuntu172.0.1+build1-0ubuntu172.0.2+build1-0ubuntu173.0+build1-0ubuntu173.0+build2-0ubuntu173.0+build3-0ubuntu173.0.1+build1-0ubuntu174.0+build1-0ubuntu174.0+build2-0ubuntu174.0+build2-0ubuntu274.0+build3-0ubuntu175.0+build3-0ubuntu1 |
76.0+build2-0ubuntu0.20.04.1 |
mozjs68Ubuntu:20.04:LTS |
All versions, plus listed versions 68.5.0-1~fakesync68.5.0-2~fakesync68.6.0-168.6.0-1ubuntu1 |
None known |
mozjs52Ubuntu:20.04:LTS |
All versions, plus listed versions 52.9.1-1build152.9.1-1ubuntu3 |
None known |
firefoxUbuntu:16.04:LTS From an advisory covering 8 CVEs |
before 76.0+build2-0ubuntu0.16.04.1, plus listed versions 41.0.2+build2-0ubuntu142.0+build2-0ubuntu144.0+build3-0ubuntu244.0.1+build1-0ubuntu144.0.2+build1-0ubuntu1 Show 45 moreShow less45.0+build2-0ubuntu145.0.1+build1-0ubuntu145.0.2+build1-0ubuntu146.0+build5-0ubuntu0.16.04.246.0.1+build1-0ubuntu0.16.04.247.0+build3-0ubuntu0.16.04.148.0+build2-0ubuntu0.16.04.149.0+build4-0ubuntu0.16.04.149.0.2+build2-0ubuntu0.16.04.250.0+build2-0ubuntu0.16.04.250.0.2+build1-0ubuntu0.16.04.150.1.0+build2-0ubuntu0.16.04.151.0.1+build2-0ubuntu0.16.04.151.0.1+build2-0ubuntu0.16.04.252.0+build2-0ubuntu0.16.04.152.0.1+build2-0ubuntu0.16.04.152.0.2+build1-0ubuntu0.16.04.153.0+build6-0ubuntu0.16.04.153.0.2+build1-0ubuntu0.16.04.253.0.3+build1-0ubuntu0.16.04.254.0+build3-0ubuntu0.16.04.155.0.1+build2-0ubuntu0.16.04.255.0.2+build1-0ubuntu0.16.04.156.0+build6-0ubuntu0.16.04.156.0+build6-0ubuntu0.16.04.257.0+build4-0ubuntu0.16.04.557.0+build4-0ubuntu0.16.04.657.0.1+build2-0ubuntu0.16.04.157.0.3+build1-0ubuntu0.16.04.157.0.4+build1-0ubuntu0.16.04.158.0+build6-0ubuntu0.16.04.158.0.1+build1-0ubuntu0.16.04.158.0.2+build1-0ubuntu0.16.04.159.0+build5-0ubuntu0.16.04.159.0.1+build1-0ubuntu0.16.04.159.0.2+build1-0ubuntu0.16.04.159.0.2+build1-0ubuntu0.16.04.360.0+build2-0ubuntu0.16.04.160.0.1+build2-0ubuntu0.16.04.160.0.2+build1-0ubuntu0.16.04.161.0+build3-0ubuntu0.16.04.261.0.1+build1-0ubuntu0.16.04.162.0+build2-0ubuntu0.16.04.362.0+build2-0ubuntu0.16.04.462.0+build2-0ubuntu0.16.04.5 |
76.0+build2-0ubuntu0.16.04.1 |
firefoxUbuntu:18.04:LTS From an advisory covering 8 CVEs |
before 76.0+build2-0ubuntu0.18.04.1, plus listed versions 56.0+build6-0ubuntu157.0.1+build2-0ubuntu159.0.1+build1-0ubuntu159.0.2+build1-0ubuntu160.0+build2-0ubuntu1 Show 40 moreShow less60.0.1+build2-0ubuntu0.18.04.160.0.2+build1-0ubuntu0.18.04.161.0+build3-0ubuntu0.18.04.161.0.1+build1-0ubuntu0.18.04.162.0+build2-0ubuntu0.18.04.362.0+build2-0ubuntu0.18.04.462.0+build2-0ubuntu0.18.04.562.0.3+build1-0ubuntu0.18.04.163.0+build2-0ubuntu0.18.04.263.0.3+build1-0ubuntu0.18.04.164.0+build3-0ubuntu0.18.04.165.0+build2-0ubuntu0.18.04.165.0.1+build2-0ubuntu0.18.04.166.0+build3-0ubuntu0.18.04.166.0.1+build1-0ubuntu0.18.04.166.0.2+build1-0ubuntu0.18.04.166.0.3+build1-0ubuntu0.18.04.166.0.4+build3-0ubuntu0.18.04.166.0.5+build1-0ubuntu0.18.04.167.0+build2-0ubuntu0.18.04.167.0.1+build1-0ubuntu0.18.04.167.0.2+build2-0ubuntu0.18.04.167.0.3+build1-0ubuntu0.18.04.167.0.4+build1-0ubuntu0.18.04.168.0+build3-0ubuntu0.18.04.168.0.1+build1-0ubuntu0.18.04.168.0.2+build1-0ubuntu0.18.04.169.0+build2-0ubuntu0.18.04.169.0.1+build1-0ubuntu0.18.04.169.0.2+build1-0ubuntu0.18.04.170.0+build2-0ubuntu0.18.04.170.0.1+build1-0ubuntu0.18.04.171.0+build5-0ubuntu0.18.04.172.0.1+build1-0ubuntu0.18.04.172.0.2+build1-0ubuntu0.18.04.173.0+build3-0ubuntu0.18.04.173.0.1+build1-0ubuntu0.18.04.174.0+build3-0ubuntu0.18.04.174.0.1+build1-0ubuntu0.18.04.175.0+build3-0ubuntu0.18.04.1 |
76.0+build2-0ubuntu0.18.04.1 |
firefoxUbuntu:20.04:LTS From an advisory covering 8 CVEs |
before 76.0+build2-0ubuntu0.20.04.1, plus listed versions 69.0.3+build1-0ubuntu170.0+build2-0ubuntu170.0+build2-0ubuntu270.0.1+build1-0ubuntu271.0+build2-0ubuntu2 Show 12 moreShow less71.0+build5-0ubuntu172.0.1+build1-0ubuntu172.0.2+build1-0ubuntu173.0+build1-0ubuntu173.0+build2-0ubuntu173.0+build3-0ubuntu173.0.1+build1-0ubuntu174.0+build1-0ubuntu174.0+build2-0ubuntu174.0+build2-0ubuntu274.0+build3-0ubuntu175.0+build3-0ubuntu1 |
76.0+build2-0ubuntu0.20.04.1 |
MozillaFirefoxopenSUSE:Tumbleweed From an advisory covering 661 CVEs |
before 92.0-1.2 | 92.0-1.2 |
firefox-esropenSUSE:Tumbleweed From an advisory covering 1860 CVEs |
before 128.5.1-1.1 | 128.5.1-1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| affected, aliases, references | OSV | |
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-12390 is a critical vulnerability (CVSS 9.8) in Mozilla Firefox, published May 7, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.62%, the 76th percentile. Fixed in firefox 76.0-r0.
References
mozilla.org/security/advisories/mfsa2020-16
bugzilla.mozilla.org/show_bug.cgi?id=1141959
nvd.nist.gov/vuln/detail/CVE-2020-12390
github.com/advisories/GHSA-2hhq-96pp-rf56
security.alpinelinux.org/vuln/CVE-2020-12390
access.redhat.com/errata/RHSA-2020:3557
Show 194 moreShow less
bugzilla.redhat.com/show_bug.cgi?id=1861645
security.access.redhat.com/data/csaf/v2/advisories/2020/rhsa-2020_3557.json
cve.org/CVERecord?id=CVE-2020-12390
ubuntu.com/security/CVE-2020-12390
suse.com/security/cve/CVE-2006-6077
lists.opensuse.org/archives/list/[email protected]/thread/3HI2RC7AJAHY74Q6MK7GNGWU6TITB22V
This page doesn't list everything
Left out here: 64 versions and 1,726 references. The JSON record has them.