CVE-2017-7783
If a long user name is used in a username/password combination in a site URL (such as " http:/...
If a long user name is used in a username/password combination in a site URL (such as " http://UserName:[email protected]"), the resulting modal prompt will hang in a non-responsive state or crash, causing a denial of service. This vulnerability affects Firefox < 55.
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
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
If a long user name is used in a username/password combination in a site URL (such as " http://UserName:[email protected]"), the resulting modal prompt will hang in a non-responsive state or crash, causing a denial of service. This vulnerability affects Firefox < 55.
- Record
CVE-2017-7783- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:N/I:N/A:P - Weakness
- CWE-20
- Updated
- 2026-11-02
CVE List No score
If a long user name is used in a username/password combination in a site URL (such as " http://UserName:[email protected]"), the resulting modal prompt will hang in a non-responsive state or crash, causing a denial of service. This vulnerability affects Firefox < 55.
- Record
CVE-2017-7783- Updated
- 2026-11-02
EUVDEUVD-2017-16758 No score
If a long user name is used in a username/password combination in a site URL (such as " http://UserName:[email protected]"), the resulting modal prompt will hang in a non-responsive state or crash, causing a denial of service. This vulnerability affects Firefox < 55.
- Record
EUVD-2017-16758- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-ch5f-5368-9hw8
If a long user name is used in a username/password combination in a site URL (such as " http:/...
If a long user name is used in a username/password combination in a site URL (such as " http://UserName:[email protected]"), the resulting modal prompt will hang in a non-responsive state or crash, causing a denial of service. This vulnerability affects Firefox < 55.
- Record
GHSA-ch5f-5368-9hw8- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-20
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2017-7783
If a long user name is used in a username/password combination in a site URL (such as " http://UserName:[email protected]"), the resulting modal prompt will hang in a non-responsive state or crash, causing a denial of service. This vulnerability affects Firefox < 55.
- Record
UBUNTU-CVE-2017-7783- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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-3391-1 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 conduct cross-site scripting (XSS) attacks, bypass sandbox restrictions, obtain sensitive information, spoof the origin of modal alerts, bypass same origin restrictions, read uninitialized memory, cause a denial of service via program crash or hang, or execute arbitrary code. (CVE-2017-7753, CVE-2017-7779, CVE-2017-7780, CVE-2017-7781, CVE-2017-7783, CVE-2017-7784, CVE-2017-7785, CVE-2017-7786, CVE-2017-7787, CVE-2017-7788, CVE-2017-7789, CVE-2017-7791, CVE-2017-7792, CVE-2017-7794, CVE-2017-7797, CVE-2017-7798, CVE-2017-7799, CVE-2017-7800, CVE-2017-7801, CVE-2017-7802, CVE-2017-7803, CVE-2017-7806, CVE-2017-7807, CVE-2017-7808, CVE-2017-7809)
- Record
USN-3391-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
firefoxUbuntu:14.04:LTS |
before 55.0.1+build2-0ubuntu0.14.04.2, plus listed versions 24.0+build1-0ubuntu125.0+build3-0ubuntu0.13.10.128.0~b2+build1-0ubuntu228.0+build1-0ubuntu128.0+build2-0ubuntu1 Show 45 moreShow less28.0+build2-0ubuntu229.0+build1-0ubuntu0.14.04.230.0+build1-0ubuntu0.14.04.331.0+build1-0ubuntu0.14.04.132.0+build1-0ubuntu0.14.04.132.0.3+build1-0ubuntu0.14.04.133.0+build2-0ubuntu0.14.04.134.0+build2-0ubuntu0.14.04.135.0+build3-0ubuntu0.14.04.235.0.1+build1-0ubuntu0.14.04.136.0+build2-0ubuntu0.14.04.436.0.1+build2-0ubuntu0.14.04.136.0.4+build1-0ubuntu0.14.04.137.0+build2-0ubuntu0.14.04.137.0.1+build1-0ubuntu0.14.04.137.0.2+build1-0ubuntu0.14.04.138.0+build3-0ubuntu0.14.04.139.0+build5-0ubuntu0.14.04.139.0.3+build2-0ubuntu0.14.04.140.0+build4-0ubuntu0.14.04.140.0+build4-0ubuntu0.14.04.440.0.3+build1-0ubuntu0.14.04.141.0+build3-0ubuntu0.14.04.141.0.1+build2-0ubuntu0.14.04.141.0.2+build2-0ubuntu0.14.04.142.0+build2-0ubuntu0.14.04.143.0+build1-0ubuntu0.14.04.143.0.4+build3-0ubuntu0.14.04.144.0+build3-0ubuntu0.14.04.144.0.1+build2-0ubuntu0.14.04.144.0.2+build1-0ubuntu0.14.04.145.0+build2-0ubuntu0.14.04.145.0.1+build1-0ubuntu0.14.04.245.0.2+build1-0ubuntu0.14.04.146.0+build5-0ubuntu0.14.04.246.0.1+build1-0ubuntu0.14.04.347.0+build3-0ubuntu0.14.04.148.0+build2-0ubuntu0.14.04.149.0+build4-0ubuntu0.14.04.149.0.2+build2-0ubuntu0.14.04.150.0+build2-0ubuntu0.14.04.250.0.2+build1-0ubuntu0.14.04.150.1.0+build2-0ubuntu0.14.04.151.0.1+build2-0ubuntu0.14.04.151.0.1+build2-0ubuntu0.14.04.2 |
55.0.1+build2-0ubuntu0.14.04.2 |
firefoxUbuntu:16.04:LTS |
before 55.0.1+build2-0ubuntu0.16.04.2, plus listed versions 41.0.2+build2-0ubuntu142.0+build2-0ubuntu144.0+build3-0ubuntu244.0.1+build1-0ubuntu144.0.2+build1-0ubuntu1 Show 21 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+build3-0ubuntu0.16.04.1 |
55.0.1+build2-0ubuntu0.16.04.2 |
mozjs38Ubuntu:18.04:LTS |
All versions, plus listed versions 38.8.0~repack1-0ubuntu138.8.0~repack1-0ubuntu338.8.0~repack1-0ubuntu4 |
None known |
MozillaFirefoxopenSUSE:Tumbleweed |
before 92.0-1.2 | 92.0-1.2 |
firefox-esropenSUSE:Tumbleweed |
before 128.5.1-1.1 | 128.5.1-1.1 |
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| Exploit-DB | Mozilla Firefox < 55 - Denial of Service | 2017-10-20 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, Exploit-DB, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2017-7783 is a high vulnerability (CVSS 7.5) in Mozilla Firefox, published August 10, 2017. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 13.8%, the 96th percentile. Fixed in firefox 55.0.1+build2-0ubuntu0.14.04.2.
References
securityfocus.com/bid/100401
bugzilla.mozilla.org/show_bug.cgi?id=1360842
mozilla.org/security/advisories/mfsa2017-18
exploit-db.com/exploits/43020
securitytracker.com/id/1039124
nvd.nist.gov/vuln/detail/CVE-2017-7783
Show 194 moreShow less
github.com/advisories/GHSA-ch5f-5368-9hw8
ubuntu.com/security/CVE-2017-7783
cve.org/CVERecord?id=CVE-2017-7783
suse.com/security/cve/CVE-2006-6077
lists.opensuse.org/archives/list/[email protected]/thread/3HI2RC7AJAHY74Q6MK7GNGWU6TITB22V
Left out here: 7 versions and 1,695 references. The JSON record has them.