cbcvebase.
CVE-2020-26958
published 2020-12-09

CVE-2020-26958: Firefox did not block execution of scripts with incorrect MIME types when the response was intercepted and cached through a ServiceWorker. This could lead to a…

PriorityP427medium6.1CVSS 3.1
AVNACLPRNUIRSCCLILAN
EPSS
1.31%
67.1th percentile
Firefox did not block execution of scripts with incorrect MIME types when the response was intercepted and cached through a ServiceWorker. This could lead to a cross-site script inclusion vulnerability, or a Content Security Policy bypass. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.

Affected

12 ranges
VendorProductVersion rangeFixed in
debianfirefox< firefox 83.0-1 (sid)firefox 83.0-1 (sid)
debianfirefox-esr< firefox 83.0-1 (sid)firefox 83.0-1 (sid)
debianthunderbird< firefox 83.0-1 (sid)firefox 83.0-1 (sid)
mozillafirefox< 8383
mozillafirefox< 83.083.0
mozillafirefox
mozillafirefox_esr< 78.578.5
mozillathunderbird< 78.578.5
mozillathunderbird>= 0 < 1:78.5.0-11:78.5.0-1
mozillathunderbird>= 0 < 1:78.5.0-11:78.5.0-1
mozillathunderbird>= 0 < 1:78.5.0-11:78.5.0-1
mozillathunderbird>= 0 < 1:78.5.0-11:78.5.0-1

CVSS provenance

nvdv3.16.1MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:N/I:P/A:N
osv6.1MEDIUM
vendor_debian6.1MEDIUM
vendor_redhat6.1MEDIUM
Stop checking back — get the weekly exploitation signal.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.