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…
- Published
- Updated
- Reserved
- Assigned by
- mozilla
Description
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.
Public exploit
A reference of the record is tagged as an exploit or proof of concept: anyone can try it against an unpatched system.
- 43020 (opens in a new tab)exploitx_refsource_EXPLOIT-DBx_transferred
Timeline
ID reserved
By mozilla
- 14 months later
· 14 months later
Published
- 6 years later
· 6 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.0 | High7.5 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 13.8% · top 3.4% of all CVEs (9 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Weakness
- DOS attack through long username in URL
- CWE-20 (opens in a new tab)All about CWE-20 and its CVEs
Affected products
References (5)
- 100401 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- https://bugzilla.mozilla.org/show_bug.cgi?id=1360842 (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://www.mozilla.org/security/advisories/mfsa2017-18/ (opens in a new tab)x_refsource_CONFIRMx_transferred
- 43020 (opens in a new tab)exploitx_refsource_EXPLOIT-DBx_transferred
- 1039124 (opens in a new tab)vdb-entryx_refsource_SECTRACKx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2017-7783)Record last updated .