Mozilla Foundation Security Advisory 2019-21

Security vulnerabilities fixed in Firefox 68

Announced July 9, 2019 Impact critical Products Firefox Fixed in Firefox 68

# CVE-2019-11711: Script injection within domain through inner window reuse Reporter Boris Zbarsky Impact high Description When an inner window is reused, it does not consider the use of document.domain for cross-origin protections. If pages on different subdomains ever cooperatively use document.domain , then either page can abuse this to inject script into arbitrary pages on the other subdomain, even those that did not use document.domain to relax their origin security. References Bug 1552541

# CVE-2019-11712: Cross-origin POST requests can be made with NPAPI plugins by following 308 redirects Reporter Gregory Smiley of Security Compass Impact high Description POST requests made by NPAPI plugins, such as Flash, that receive a status 308 redirect response can bypass CORS requirements. This can allow an attacker to perform Cross-Site Request Forgery (CSRF) attacks. References Bug 1543804

# CVE-2019-11713: Use-after-free with HTTP/2 cached stream Reporter Hanno Böck Impact high Description A use-after-free vulnerability can occur in HTTP/2 when a cached HTTP/2 stream is closed while still in use, resulting in a potentially exploitable crash. References Bug 1528481

# CVE-2019-11714: NeckoChild can trigger crash when accessed off of main thread Reporter Hanno Böck Impact moderate Description Necko can access a child on the wrong thread during UDP connections, resulting in a potentially exploitable crash in some instances. References Bug 1542593

# CVE-2019-11729: Empty or malformed p256-ECDH public keys may trigger a segmentation fault Reporter Jonas Allmann Impact moderate Description Empty or malformed p256-ECDH public keys may trigger a segmentation fault due values being improperly sanitized before being copied into memory and used. References Bug 1515342

# CVE-2019-11715: HTML parsing error can contribute to content XSS Reporter Linus Särud Impact moderate Description Due to an error while parsing page content, it is possible for properly sanitized user input to be misinterpreted and lead to XSS hazards on web sites in certain circumstances. References Bug 1555523

# CVE-2019-11716: globalThis not enumerable until accessed Reporter Chris Hacking Impact moderate Description Until explicitly accessed by script, window.globalThis is not enumerable and, as a result, is not visible to code such as Object.getOwnPropertyNames(window) . Sites that deploy a sandboxing that depends on enumerating and freezing access to the window object may miss this, allowing their sandboxes to be bypassed. References Bug 1552632

# CVE-2019-11717: Caret character improperly escaped in origins Reporter Tyson Smith Impact moderate Description A vulnerability exists where the caret ("^") character is improperly escaped constructing some URIs due to it being used as a separator, allowing for possible spoofing of origin attributes. References Bug 1548306

# CVE-2019-11718: Activity Stream writes unsanitized content to innerHTML Reporter Mark Banner Impact moderate Description Activity Stream can display content from sent from the Snippet Service website. This content is written to innerHTML on the Activity Stream page without sanitization, allowing for a potential access to other information available to the Activity Stream, such as browsing history, if the Snipper Service were compromised. References Bug 1408349

# CVE-2019-11719: Out-of-bounds read when importing curve25519 private key Reporter Henry Corrigan-Gibbs Impact moderate Description When importing a curve25519 private key in PKCS#8format with leading 0x00 bytes, it is possible to trigger an out-of-bounds read in the Network Security Services (NSS) library. This could lead to information disclosure. References Bug 1540541

# CVE-2019-11720: Character encoding XSS vulnerability Reporter Rakesh Mane Impact moderate Description Some unicode characters are incorrectly treated as whitespace during the parsing of web content instead of triggering parsing errors. This allows malicious code to then be processed, evading cross-site scripting (XSS) filtering. References Bug 1556230

# CVE-2019-11721: Domain spoofing through unicode latin 'kra' character Reporter Anonymous Impact moderate Description The unicode latin 'kra' character can be used to spoof a standard 'k' character in the addressbar. This allows for domain spoofing attacks as do not display as punycode text, allowing for user confusion. References Bug 1256009

# CVE-2019-11730: Same-origin policy treats all files in a directory as having the same-origin Reporter Luigi Gubello Impact moderate Description A vulnerability exists where if a user opens a locally saved HTML file, this file can use file: URIs to access other files in the same directory or sub-directories if the names are known or guessed. The Fetch API can then be used to read the contents of any files stored in these directories and they may uploaded to a server. Luigi Gubello demonstrated that in combination with a popular Android messaging app, if a malicious HTML attachment is sent to a user and they opened that attachment in Firefox, due to that app's predictable pattern for locally-saved file names, it is possible to read attachments the victim received from other correspondents. References Bug 1558299

# CVE-2019-11723: Cookie leakage during add-on fetching across private browsing boundaries Reporter Andreas Wagner Impact low Description A vulnerability exists during the installation of add-ons where the initial fetch ignored the origin attributes of the browsing context. This could leak cookies in private browsing mode or across different "containers" for people who use the Firefox Multi-Account Containers Web Extension. References Bug 1528335

# CVE-2019-11724: Retired site input.mozilla.org has remote troubleshooting permissions Reporter Frederik Braun Impact low Description Application permissions give additional remote troubleshooting permission to the site input.mozilla.org, which has been retired and now redirects to another site. This additional permission is unnecessary and is a potential vector for malicious attacks. References Bug 1512511

# CVE-2019-11725: Websocket resources bypass safebrowsing protections Reporter Andrey Impact low Description When a user navigates to site marked as unsafe by the Safebrowsing API, warning messages are displayed and navigation is interrupted but resources from the same site loaded through websockets are not blocked, leading to the loading of unsafe resources and bypassing safebrowsing protections. References Bug 1483510

# CVE-2019-11727: PKCS#1 v1.5 signatures can be used for TLS 1.3 Reporter Hubert Kario Impact low Description A vulnerability exists where it possible to force Network Security Services (NSS) to sign CertificateVerify with PKCS#1 v1.5 signatures when those are the only ones advertised by server in CertificateRequest in TLS 1.3. PKCS#1 v1.5 signatures should not be used for TLS 1.3 messages. References Bug 1552208

# CVE-2019-11728: Port scanning through Alt-Svc header Reporter Trishita Tiwari, Ari Trachtenberg Impact low Description The HTTP Alternative Services header, Alt-Svc , can be used by a malicious site to scan all TCP ports of any host that the accessible to a user when web content is loaded. References Bug 1552993

# CVE-2019-11710: Memory safety bugs fixed in Firefox 68 Reporter Mozilla developers and community Impact critical Description Mozilla developers and community members André Bargull, Christian Holler, Natalia Csoregi, Raul Gurzau, Daniel Varga, Jon Coppeard, Marcia Knous, Gary Kwong, Randell Jesup, David Bolter, Jeff Gilbert, and Deian Stefan reported memory safety bugs present in Firefox 67. 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. References Memory safety bugs fixed in Firefox 68