CVE-2017-5449
A possibly exploitable crash triggered during layout and manipulation of bidirectional unicode text in concert with CSS animations.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (2.51%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
A possibly exploitable crash triggered during layout and manipulation of bidirectional unicode text in concert with CSS animations. This vulnerability affects Thunderbird < 52.1, Firefox ESR < 52.1, and Firefox < 53.
- CVSS 3.0
- 7.5 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 2.51% probability · 85th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-20
- Affected
- redhat/enterprise linux · 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
- Source
- security@mozilla.org
EPSS 2.5% 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/97940Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1038320Third Party Advisory, VDB Entry
- https://access.redhat.com/errata/RHSA-2017:1104Third Party Advisory
- https://access.redhat.com/errata/RHSA-2017:1106Third Party Advisory
- https://access.redhat.com/errata/RHSA-2017:1201Third Party Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1340127Issue Tracking, Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-10/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-12/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-13/Vendor Advisory
- http://www.securityfocus.com/bid/97940Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1038320Third Party Advisory, VDB Entry
- https://access.redhat.com/errata/RHSA-2017:1104Third Party Advisory
- https://access.redhat.com/errata/RHSA-2017:1106Third Party Advisory
- https://access.redhat.com/errata/RHSA-2017:1201Third Party Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1340127Issue Tracking, Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-10/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-12/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-13/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.