dbcve.org
FedoraOperating system · Fedoraproject

CVE-2015-7218

MEDIUM · 5.0 CVSS v2.0 Published 2015-12-16
Fix available
A fix is available. Upgrade to after 42.0 or later.
See remediation →
59/100
Remediation priority · Elevated
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
The HTTP/2 implementation in Mozilla Firefox before 43.0 allows remote attackers to cause a denial of service (integer underflow, assertion failure, and application exit) via a single-byte header frame that triggers incorrect memory allocation.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

The HTTP/2 implementation in Mozilla Firefox before 43.0 contains an integer underflow vulnerability triggered by a single-byte header frame. This causes incorrect memory allocation leading to assertion failure and application exit (denial of service).

MitigationUpgrade Firefox to version 43.0 or later. In enterprise environments, deploy the updated version via standard software distribution mechanisms.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
FedoraOperating system
Affected:= 22= 23
FirefoxWeb browser
Affected:<= 42.0
LeapOperating system
Affected:= 42.1
OpensuseOperating system
Affected:= 13.1= 13.2

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Authentication
None
Confidentiality
None
Integrity
None
Availability
Partial

AV:N/AC:L/Au:N/C:N/I:N/A:P

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify installed Firefox version
    Run 'firefox --version' from command line, or in Firefox go to Help > About Firefox
    Affected if Version is 42.0 or lower
  2. Check HTTP/2 protocol support is enabled
    In Firefox address bar, enter 'about:config', then search for 'network.http.spdy.enabled.http2' and verify the value
    Affected if The network.http.spdy.enabled.http2 preference is set to true (enabled)
  3. Confirm operating system if using Linux distribution
    Run 'cat /etc/os-release' or 'cat /etc/fedora-release' for Fedora, 'cat /etc/os-release' for openSUSE
    Affected if Running Fedora 22 or 23, or openSUSE 13.1, 13.2, or Leap 42.1 with Firefox 42.0 or lower installed

A user is affected if they are running Firefox version 42.0 or earlier with HTTP/2 protocol support enabled on any of the listed operating system versions.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Upgrade available Upgrade to a release after 42.0
Interim mitigation

Upgrade Firefox to version 43.0 or later. In enterprise environments, deploy the updated version via standard software distribution mechanisms.

Fix this in Fedora Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,560.

Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2015-7218 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data