Firefox
CVE-2018-12383
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V6 - Authentication Credential protection in transit/storage
|
| Impact | CVSS score of 5.5 (MEDIUM). Attack characteristics: local attack vector, low complexity, low privileges required, no user interaction not required. Public proof-of-concept exploit code is available. |
| Exploit ScenarioDerived | A local attacker with access to the system could obtain user credentials due to weak protection mechanisms. |
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Alert meAnalysisAI
If a user saved passwords before Firefox 58 and then later set a master password, an unencrypted copy of these passwords is still accessible. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. Public exploit code available and no vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Hash passwords with strong algorithms (bcrypt, argon2), encrypt credentials in transit and at rest, never log credentials.
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Technical ContextAI · show details
This vulnerability is classified as Insufficiently Protected Credentials (CWE-522), which allows attackers to obtain user credentials due to weak protection mechanisms. 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. Affected products include: Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Server, Redhat Enterprise Linux Server Aus, Redhat Enterprise Linux Server Eus, Redhat Enterprise Linux Server Tus.
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Severity by source
AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
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.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.
Affected Products (CPE)NVD
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The XrayWrapper implementation in Mozilla Firefox before 35.0 and SeaMonkey before 2.32 does not properly interact with
The Chrome Object Wrapper (COW) implementation in Mozilla Firefox before 18.0, Firefox ESR 17.x before 17.0.2, Thunderbi
The Web IDL implementation in Mozilla Firefox before 28.0, Firefox ESR 24.x before 24.4, Thunderbird before 24.4, and Se
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NVD
CVE.org
EPSS
GitHub PoC
Exploit-DB