CVE-2017-7783

critical

Published — · Modified —

💬 Discuss on Community ✚ Propose mitigation

CVSS v3

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CVSS v4 NEW

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not yet in upstream

VIR risk

10.0

Description

If a long user name is used in a username/password combination in a site URL (such as " http://UserName:Password@example.com"), the resulting modal prompt will hang in a non-responsive state or crash, causing a denial of service. This vulnerability affects Firefox < 55.

Predictions

Exploit likelihood

20%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

Exploits

Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.

Exploit-DB

EDB-43020 dos multiple verified

Amit Sangra · 2017-10-20

Mozilla Firefox < 55 - Denial of Service

Source code queued for fetch — refresh in a moment.

OS impact

OS	Version	Status	Fixed in
arch		fixed	`55.0-1`
sles		affected
debian	sid	fixed	`55.0-1`

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.