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CVE Record

CVE-2017-5442: A use-after-free vulnerability during changes in style when manipulating DOM elements.

A use-after-free vulnerability during changes in style when manipulating DOM elements. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 52.1, Firefox ESR < 45.9, Firefox ESR < 52.1, and Firefox < 53.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

CVE-2017-5442 is a Mozilla memory-safety flaw where crafted web content could trigger a use-after-free during style changes on DOM elements. Sources describe it as a potentially exploitable crash affecting old Firefox, Firefox ESR, and Thunderbird releases. Modern patched versions should not be affected by the version ranges listed.

Executive priority

Prioritize remediation if any legacy Mozilla clients remain in production or privileged user environments. The issue is old, but memory-safety browser bugs can carry high impact when outdated software is still used.

Technical view

The issue is a use-after-free in Mozilla code paths handling style changes while DOM elements are manipulated. The affected ranges are Thunderbird before 52.1, Firefox ESR before 45.9 and 52.1, and Firefox before 53. The bundle provides no CVSS, CWE, or exploit details.

Likely exposure

Exposure is most likely on legacy systems running the affected Mozilla versions, especially browsers or mail clients that process untrusted web or HTML content. Current enterprise risk depends on whether old Firefox ESR or Thunderbird builds remain installed.

Exploitation context

The source bundle states a potentially exploitable crash, but provides no weaponized exploit detail. KEV is false, and no cited source in the bundle states active exploitation. Treat this as a memory-corruption risk for unsupported legacy clients.

Researcher notes

The bundle does not include CVSS, CWE mapping, root-cause detail beyond use-after-free, or active exploitation evidence. Analysis should stay tied to Mozilla and vendor advisories, and validation should focus on version inventory and patch status.

Mitigation direction

  • Upgrade Firefox to 53 or later.
  • Upgrade Firefox ESR to 45.9, 52.1, or later supported ESR.
  • Upgrade Thunderbird to 52.1 or later.
  • Check Mozilla and OS vendor advisories for package-specific guidance.
  • Retire unsupported browser and mail-client versions.

Validation and detection

  • Inventory installed Firefox, Firefox ESR, and Thunderbird versions.
  • Flag versions below the affected-version cutoffs.
  • Check Linux vendor errata coverage for managed packages.
  • Confirm browser and mail-client updates are deployed.
  • Review legacy systems that still process HTML email or web content.
Prepared
Confidence
high
Sources
10

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

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CVE-2017-5442 mapping review

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
0Timeline events
0ADP providers
10Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
MozillaThunderbirdunspecifiedListed
MozillaFirefox ESRunspecified, unspecifiedListed
MozillaFirefoxunspecifiedListed
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.