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Multiple serious vulnerabilities have been found in Firefox and Firefox ESR. Malicious users can exploit these vulnerabilities to cause denial of service, bypass security restrictions, spoof user interface, perform cross-site scripting, gain privileges and execute arbitrary code.

  1. A use-after-free vulnerability can be exploited remotely to cause denial of service;
  2. A vulnerability in Resource Timing API can be exploited remotely via service error to bypass security restrictions;
  3. A vulnerability in security wrapper can be exploited remotely via deprecated exposedProps mechanism to bypass security restrictions;
  4. An error in rendering of character ‘i’ in addressbar cat be exploited remotely via forgery of domain names to spoof user interface;
  5. A vulnerability related to rendering of some fonts can be exploited remotely to bypass security restrictions;
  6. A vulnerability related to data:URL loading can be exploited remotely via Content Security Policy to perform cross-site scripting;
  7. A vulnerability in secure mixed blocking can be exploited remotely to bypass security restrictions;;
  8. A vulnerability in Firefox Health Report can be exploited locally via “pingsender” executable to gain privileges;
  9. A vulnerability in SVG can be exploited remotely via setting of cookies to bypass security restrictions;
  10. A vulnerability in Punycode can be exploited remotely to spoof user interface;
  11. A vulnerability related to javascript:URLS pasting can be exploited to perform self-cross-site scripting;
  12. A vulnerability related to Referrer Policy attribute can be exploited via network requests to bypass security restrictions;
  13. Multiple memory corruption vulnerabilities which occur because of memory safety bugs can be exploited remotely to execute arbitrary code;

Technical details

Vulnerability (8) only affects Firefox for OS X and Linux. Other operating systems are not affected.

Vulnerability (13) only affects Mozilla Firefox 56 and Firefox ESR 52.4.

Vulnerability (7) occurs in redirecting from HTTPS to HTTP

Vulnerabilities 1,2,13 are related to Mozilla Firefox ESR.

All vulnerabilities are related to Mozilla Firefox.

NB: This vulnerabilities does not have any public CVSS rating, so rating can be changed by the time.

Original advisories

Related products

CVE list

  • CVE-2017-7827
  • CVE-2017-7826
  • CVE-2017-7828
  • CVE-2017-7830
  • CVE-2017-7831
  • CVE-2017-7832
  • CVE-2017-7833
  • CVE-2017-7834
  • CVE-2017-7835
  • CVE-2017-7836
  • CVE-2017-7837
  • CVE-2017-7838
  • CVE-2017-7839
  • CVE-2017-7840
  • CVE-2017-7842

Read more

Find out the statistics of the vulnerabilities spreading in your region on statistics.securelist.com

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