Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2018-5131

17
FAUCET Score

CVE-2018-5131 describes a vulnerability in Firefox and Firefox ESR where the "fetch()" API could improperly return locally cached resources, even if marked "no-store" or "no-cache," instead of fetching fresh copies from the network. This could expose previously stored, sensitive data to other users sharing a browser profile. With a CVSS score of 5.9 (Medium), this vulnerability has a network attack vector and high confidentiality impact, but requires high attack complexity. There is no evidence of active exploitation, public exploit code, or significant community discussion surrounding this CVE.

Impacted Technologies

VendorProductVersion(s)CPE
7.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:*
8.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
9.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
< 59.0CPE matchmatch criteria
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
< 52.7.0CPE matchmatch criteria
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.0

5.9MEDIUM

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

Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
NONE
Availability Impact
NONE
Exploitability Score
2.2
Impact Score
3.6
CvssVersion
3.0

Exploit Intelligence

EPSS Score
2.32%
Probability of exploitation in next 30 days
EPSS Percentile
81.7%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0232 is in the 70th percentile among its peer group of 19,958 CVEs.

Social Chatter

No social media mentions found for this CVE.

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.0 Bluesky, 0.0 Mastodon, and 0.2 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

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

Remediation

Patch Available

Vendor Patches (3)

redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 6Fixed in: firefox-0:52.7.0-1.el6_9
View patch
redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 7Fixed in: firefox-0:52.7.0-1.el7_4
View patch
mozillavendor investigatingvia nvd_reference
View patch

Vendor Advisories (1)

redhatCVE-2018-5131Moderate

Mozilla: Fetch API improperly returns cached copies of no-store/no-cache resources (MFSA 2018-07)

Mar 14, 2018

References

access.redhat.com / errata/RHSA-2018:0526
Third Party Advisory
access.redhat.com / errata/RHSA-2018:0527
Third Party Advisory
bugzilla.mozilla.org / show_bug.cgi
Issue TrackingPermissions RequiredThird Party Advisory
lists.debian.org / debian-lts-announce/2018/03/msg00010.html
Third Party Advisory
security.gentoo.org / glsa/201810-01
Third Party Advisory
usn.ubuntu.com / 3596-1
Third Party Advisory
debian.org / security/2018/dsa-4139
Third Party Advisory
mozilla.org / security/advisories/mfsa2018-06
Vendor Advisory
mozilla.org / security/advisories/mfsa2018-07
Vendor Advisory
securityfocus.com / bid/103388
Third Party AdvisoryVDB Entry
securitytracker.com / id/1040514
Third Party AdvisoryVDB Entry