CVE-2017-5403
This triggers a use-after-free, resulting in a potentially exploitable crash.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.66%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
When adding a range to an object in the DOM, it is possible to use "addRange" to add the range to an incorrect root object. This triggers a use-after-free, resulting in a potentially exploitable crash. This vulnerability affects Firefox < 52 and Thunderbird < 52.
- CVSS 3.0
- 9.8 CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.66% probability · 77th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-416
- Affected
- mozilla/thunderbird · mozilla/firefox
- Source
- security@mozilla.org
EPSS 1.7% 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/96691Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1037966Third Party Advisory, VDB Entry
- https://bugzilla.mozilla.org/show_bug.cgi?id=1340186Issue Tracking, Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-05/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-09/Vendor Advisory
- http://www.securityfocus.com/bid/96691Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1037966Third Party Advisory, VDB Entry
- https://bugzilla.mozilla.org/show_bug.cgi?id=1340186Issue Tracking, Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-05/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-09/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.