CVE-2017-7784
A use-after-free vulnerability can occur when reading an image observer during frame reconstruction after the observer has been freed.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (3.50%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
A use-after-free vulnerability can occur when reading an image observer during frame reconstruction after the observer has been freed. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 52.3, Firefox ESR < 52.3, and Firefox < 55.
- 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
- 3.50% probability · 89th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-416
- Affected
- debian/debian linux · 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/thunderbird · mozilla/firefox · mozilla/firefox esr
- Source
- security@mozilla.org
EPSS 3.5% 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/100202Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1039124Third Party Advisory, VDB Entry
- https://access.redhat.com/errata/RHSA-2017:2456Third Party Advisory
- https://access.redhat.com/errata/RHSA-2017:2534Third Party Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1376087Exploit, Issue Tracking, Vendor Advisory
- https://security.gentoo.org/glsa/201803-14Third Party Advisory
- https://www.debian.org/security/2017/dsa-3928Third Party Advisory
- https://www.debian.org/security/2017/dsa-3968Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-18/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-19/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-20/Vendor Advisory
- http://www.securityfocus.com/bid/100202Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1039124Third Party Advisory, VDB Entry
- https://access.redhat.com/errata/RHSA-2017:2456Third Party Advisory
- https://access.redhat.com/errata/RHSA-2017:2534Third Party Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1376087Exploit, Issue Tracking, Vendor Advisory
- https://security.gentoo.org/glsa/201803-14Third Party Advisory
- https://www.debian.org/security/2017/dsa-3928Third Party Advisory
- https://www.debian.org/security/2017/dsa-3968Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-18/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-19/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-20/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.