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CVE Record

CVE-2017-7826: Memory safety bugs were reported in Firefox 56 and Firefox ESR 52.4.

Memory safety bugs were reported in Firefox 56 and Firefox ESR 52.4. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code. This vulnerability affects Firefox < 57, Firefox ESR < 52.5, and Thunderbird < 52.5.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

CVE-2017-7826 covers Mozilla memory safety bugs in Firefox 56 and Firefox ESR 52.4. Mozilla reported evidence of memory corruption and believed some bugs could be exploitable for arbitrary code execution. Organizations still running affected browsers or Thunderbird builds should treat this as a legacy software risk requiring version verification and upgrade.

Executive priority

Prioritize remediation where affected Mozilla software is still present. The issue is old, but arbitrary code execution risk in browsers and mail clients remains business-relevant if legacy systems persist.

Technical view

Affected products are Firefox before 57, Firefox ESR before 52.5, and Thunderbird before 52.5. The record groups multiple memory safety defects with observed memory corruption. No CVSS or CWE detail is provided, so exact bug classes and attack preconditions are not established in the source bundle.

Likely exposure

Exposure is most likely in legacy desktops, servers with old GUI packages, unsupported gold images, or long-lived Linux distributions that retained vulnerable Firefox ESR or Thunderbird packages without security updates.

Exploitation context

The source bundle does not show CISA KEV listing or cited active exploitation. Mozilla stated some bugs could likely be exploited to run arbitrary code with enough effort, but the provided evidence does not confirm real-world exploitation.

Researcher notes

Treat this as a grouped Mozilla memory safety advisory rather than a single precisely described bug. The bundle references Mozilla MFSA advisories and distribution updates, but lacks CVSS, CWE mapping, exploit confirmation, and detailed per-bug reachability context.

Mitigation direction

  • Upgrade Firefox to 57 or later where applicable.
  • Upgrade Firefox ESR to 52.5 or later.
  • Upgrade Thunderbird to 52.5 or later.
  • Apply vendor or Linux distribution security updates for Mozilla packages.
  • Check Mozilla and OS vendor advisories for environment-specific guidance.

Validation and detection

  • Inventory Firefox, Firefox ESR, and Thunderbird versions across endpoints.
  • Confirm no Firefox versions earlier than 57 remain installed.
  • Confirm no Firefox ESR or Thunderbird versions earlier than 52.5 remain installed.
  • Review package manager history for Debian, Ubuntu, or Red Hat security updates.
  • Check exception lists for legacy application dependencies requiring old browsers.
Prepared
Confidence
medium
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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description · low confidence lookup

Execution behavior lookup

The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.

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cve · low confidence lookup

CVE-2017-7826 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
13Source 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
MozillaFirefoxunspecifiedListed
MozillaFirefox ESRunspecifiedListed
MozillaThunderbirdunspecifiedListed
Weakness

CWE details

No CWE listed

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