A flaw was found in GStreamer's adaptive streaming demuxers (HLS, DASH, MSS). When processing a media playlist or manifest, URIs referenced in the manifest content are fetched without restricting which URI schemes are permitted. An attacker who controls a manifest URL, or who can inject content into an HTTP manifest response, can include file:// URIs pointing to arbitrary local files, causing the affected application to read and process those files. In automated or server-side deployments such as media recorders, proxies, and downloaders, this can lead to disclosure of sensitive local files. Existence of files can also be inferred through differing error responses even when content is not directly observable.
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Attack patterns (CAPEC)
CAPEC-13 Subverting Environment Variable Values Likelihood: High · Severity: Very High
CAPEC-64 Using Slashes and URL Encoding Combined to Bypass Validation Logic Likelihood: High · Severity: High
CAPEC-72 URL Encoding Likelihood: High · Severity: High
CAPEC-76 Manipulating Web Input to File System Calls Likelihood: High · Severity: Very High
CAPEC-78 Using Escaped Slashes in Alternate Encoding Likelihood: High · Severity: High
CAPEC-79 Using Slashes in Alternate Encoding Likelihood: High · Severity: High
CAPEC-80 Using UTF-8 Encoding to Bypass Validation Logic Likelihood: High · Severity: High
CAPEC-267 Leverage Alternate Encoding Likelihood: High · Severity: High
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.