CVE-2023-4583

22

FAUCET Score

CVE-2023-4583 is a vulnerability in Mozilla Firefox, Firefox ESR, and Thunderbird versions prior to 117 and 115.2 respectively. It stems from an incorrect assumption within the HttpBaseChannel regarding discarded browsing contexts, potentially leading to security bypasses in private browsing sessions. Rated with a CVSS score of 7.5 (HIGH), this vulnerability is network-exploitable with low attack complexity, allowing for high integrity impact without user interaction. Currently, there is no evidence of active exploitation, public exploit code, or significant community discussion surrounding this CVE.

Impacted Technologies

Vendor	Product	Version(s)	CPE
		< 117.0CPE matchmatch criteria	cpe:2.3:a:mozilla:firefox::::::::
		< 115.2CPE matchmatch criteria	cpe:2.3:a:mozilla:firefox_esr::::::::
		< 115.2CPE matchmatch criteria	cpe:2.3:a:mozilla:thunderbird::::::::

CVSS Data

CVSS version used by this source: 3.1

7.5HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

HIGH

Availability Impact

NONE

Exploitability Score

3.9

Impact Score

3.6

CvssVersion

3.1

Exploit Intelligence

EPSS Score

0.67%

Probability of exploitation in next 30 days

EPSS Percentile

48.4%

Percentile rank of EPSS score among Peer Group

As of 2026-07-27

Model: v2026.06.15

This CVE's current EPSS score of 0.0067 is in the 25th percentile among its peer group of 51,551 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.4 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (24)

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 9.0 Extended Update SupportFixed in: firefox-0:102.15.0-1.el9_0

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 7Fixed in: thunderbird-0:102.15.0-1.el7_9

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 7Fixed in: firefox-0:102.15.0-1.el7_9

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8Fixed in: firefox-0:102.15.0-1.el8_8

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8Fixed in: thunderbird-0:102.15.0-1.el8_8

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.1 Update Services for SAP SolutionsFixed in: thunderbird-0:102.15.0-1.el8_1

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.1 Update Services for SAP SolutionsFixed in: firefox-0:102.15.0-1.el8_1

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.2 Advanced Update SupportFixed in: thunderbird-0:102.15.0-1.el8_2

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.2 Advanced Update SupportFixed in: firefox-0:102.15.0-1.el8_2

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.2 Telecommunications Update ServiceFixed in: thunderbird-0:102.15.0-1.el8_2

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.2 Telecommunications Update ServiceFixed in: firefox-0:102.15.0-1.el8_2

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.2 Update Services for SAP SolutionsFixed in: thunderbird-0:102.15.0-1.el8_2

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.2 Update Services for SAP SolutionsFixed in: firefox-0:102.15.0-1.el8_2

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update SupportFixed in: thunderbird-0:102.15.0-1.el8_4

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update SupportFixed in: firefox-0:102.15.0-1.el8_4

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.4 Telecommunications Update ServiceFixed in: thunderbird-0:102.15.0-1.el8_4

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.4 Telecommunications Update ServiceFixed in: firefox-0:102.15.0-1.el8_4

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.4 Update Services for SAP SolutionsFixed in: thunderbird-0:102.15.0-1.el8_4

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.4 Update Services for SAP SolutionsFixed in: firefox-0:102.15.0-1.el8_4

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8.6 Extended Update SupportFixed in: firefox-0:102.15.0-1.el8_6

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 9Fixed in: thunderbird-0:102.15.0-1.el9_2

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 9Fixed in: firefox-0:102.15.0-1.el9_2

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 9.0 Extended Update SupportFixed in: thunderbird-0:102.15.0-1.el9_0

mozillavendor investigatingvia nvd_reference

Vendor Advisories (2)

microsoft2023-Sep/CVE-2023-4583

When checking if the Browsing Context had been discarded in `HttpBaseChannel`, if the load group was not available then it was assumed to have already been discarded which was not always the case for private channels after the private session had ended. This vulnerability affects Firefox < 117, Firefox ESR < 115.2, and Thunderbird < 115.2.

redhatCVE-2023-4583Low

Mozilla: Browsing Context potentially not cleared when closing Private Window

References

bugzilla.mozilla.org / show_bug.cgi

Issue Tracking

mozilla.org / security/advisories/mfsa2023-34

Vendor Advisory

mozilla.org / security/advisories/mfsa2023-36

Vendor Advisory

mozilla.org / security/advisories/mfsa2023-38

Vendor Advisory