CVE-2018-12383

Description

From CVE.org

If a user saved passwords before Firefox 58 and then later set a master password, an unencrypted copy of these passwords is still accessible. This is because the older stored password file was not deleted when the data was copied to a new format starting in Firefox 58. The new master password is added only on the new file. This could allow the exposure of stored password data outside of user expectations. This vulnerability affects Firefox < 62, Firefox ESR < 60.2.1, and Thunderbird < 60.2.1.

Statement

Upstream decided to not fix this issue in Firefox ESR 60.2 given the low impact. A future ESR update may correct this flaw.

This flaw would impact users who had saved passwords from Firefox 58 or earlier that were not protected by a master password (resulting in an un-encrypted key3.db), but set a master password when using Firefox 59 or newer (resulting in an encrypted key4.db). The old key file was kept around to facilitate downgrading to Firefox 58.

This flaw cannot be exploited through email in Thunderbird as scripting is disabled in this for email content. It may be possible to exploit through Feeds (Atom or RSS) or other browser-like contexts.

Mitigation

To mitigate against this flaw, examine user profile directories for the presence of both `key3.db` and `key4.db` files. If both are present, `key3.db` should be deleted.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score5.55.5N/A
Attack VectorLocalLocalN/A
Attack ComplexityLowLowN/A
Privileges RequiredLowLowN/A
User InteractionNoneNoneN/A
ScopeUnchangedUnchangedN/A
ConfidentialityHighHighN/A
Integrity ImpactNoneNoneN/A
Availability ImpactNoneNoneN/A

Vector

Red Hat: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

NVD: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Understanding the Weakness (CWE)

Confidentiality

Technical Impact: Read Files or Directories; Read Application Data

Sensitive data may be exposed to an unauthorized actor in another control sphere. This may have a wide range of secondary consequences that will depend on what data is exposed. One possibility is the exposure of system data - such as file locations, software versions, or device data - that allow an attacker to craft a specific, more effective attack. Alternately, insufficient redaction of Private Personal Information (PPI), Personally Identifiable Information (PII), or other types of information might not harm the secure operation of the product itself, but could be violations of expectations by the product's users.

Acknowledgements

Red Hat would like to thank the Mozilla project for reporting this issue. Upstream acknowledges Jurgen Gaeremyn as the original reporter.

Frequently Asked Questions

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