SARA / Free Tools / CVE / CVE-2018-12395

CVE-2018-12395 — By rewriting the Host: request headers using the webRequest API, a WebExtension

By rewriting the Host: request headers using the webRequest API, a WebExtension can bypass domain restrictions through domain fronting. This would allow access to domains that share a host that are otherwise restricted. This vulnerability affects Firefox ESR < 60.3 and Firefox

CVSS
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EPSS
2.92% (top 13.80%)
CWE
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Published
2019-02-28T18:00:00.000Z
Last modified
2024-08-05T08:30:59.771Z
CVSS vector
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01What is this vulnerability?

By rewriting the Host: request headers using the webRequest API, a WebExtension can bypass domain restrictions through domain fronting. This would allow access to domains that share a host that are otherwise restricted. This vulnerability affects Firefox ESR < 60.3 and Firefox < 63.

02Affected products

VendorProductVersions
MozillaFirefox ESRunspecified
MozillaFirefoxunspecified

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

09References

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