CVE-2017-7814
File downloads encoded with "blob:" and "data:" URL elements bypassed normal file download checks though the Phishing and Malware Protection feature and its block lists of suspicious sites and files.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.19%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
File downloads encoded with "blob:" and "data:" URL elements bypassed normal file download checks though the Phishing and Malware Protection feature and its block lists of suspicious sites and files. This would allow malicious sites to lure users into downloading executables that would otherwise be detected as suspicious. This vulnerability affects Firefox < 56, Firefox ESR < 52.4, and Thunderbird < 52.4.
- CVSS 3.0
- 7.8 HIGHCVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- EPSS
- 1.19% probability · 68th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-20
- Affected
- redhat/enterprise linux desktop · redhat/enterprise linux server · redhat/enterprise linux server aus · redhat/enterprise linux server eus · redhat/enterprise linux workstation · mozilla/firefox · mozilla/thunderbird · debian/debian linux
- Source
- security@mozilla.org
EPSS 1.2% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://www.securityfocus.com/bid/101059Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1039465Third Party Advisory, VDB Entry
- https://access.redhat.com/errata/RHSA-2017:2831Third Party Advisory
- https://access.redhat.com/errata/RHSA-2017:2885Third Party Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1376036Issue Tracking, Patch, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2017/11/msg00000.htmlThird Party Advisory
- https://security.gentoo.org/glsa/201803-14Third Party Advisory
- https://www.debian.org/security/2017/dsa-3987Third Party Advisory
- https://www.debian.org/security/2017/dsa-4014Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-21/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-22/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-23/Vendor Advisory
- http://www.securityfocus.com/bid/101059Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1039465Third Party Advisory, VDB Entry
- https://access.redhat.com/errata/RHSA-2017:2831Third Party Advisory
- https://access.redhat.com/errata/RHSA-2017:2885Third Party Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1376036Issue Tracking, Patch, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2017/11/msg00000.htmlThird Party Advisory
- https://security.gentoo.org/glsa/201803-14Third Party Advisory
- https://www.debian.org/security/2017/dsa-3987Third Party Advisory
- https://www.debian.org/security/2017/dsa-4014Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-21/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-22/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-23/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.