Copier Org
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Copier CLI and library versions 9.5.0 through 9.16.0 expose a trust-prefix bypass that permits unsafe template features from untrusted repositories to execute on a victim's system after user interaction. The vulnerability arises because Copier's trusted-repository prefix check evaluates the raw percent-encoded URL string, while the underlying HTTP or Git transport subsequently decodes it - meaning a URL containing encoded dot-dot segments (e.g., %2e%2e) or encoded separators (%2f, %5c) can appear to match a trusted prefix while actually resolving to an entirely different, attacker-controlled repository. No active exploitation has been confirmed (not in CISA KEV) and no public exploit code was identified in the provided data; the issue is patched in v9.17.0.
Trust-boundary bypass in Copier 9.5.0 through 9.15.1 lets an attacker-controlled template execute arbitrary commands without the usual --trust confirmation. The flaw stems from the trust prefix check using a raw str.startswith on the un-normalized template URL, so a reference that textually begins with a trusted prefix but contains '..' is granted trust while actually resolving to a different template whose tasks/migrations/jinja_extensions then run. No public exploit identified at time of analysis, and it is not in CISA KEV; fixed in 9.15.2.
Copier versions prior to 9.11.2 allow local attackers to write arbitrary files outside the intended project destination directory by exploiting symlink handling combined with the _preserve_symlinks feature in ostensibly safe templates. A malicious template author can craft a project template that bypasses security controls without requiring unsafe flags, enabling arbitrary file overwrites within the user's write permissions. Public exploit code exists for this vulnerability.
Copier versions before 9.11.2 allow local attackers to read arbitrary files outside the template directory by exploiting symlink handling when the default `_preserve_symlinks: false` setting is enabled, bypassing the library's safety guarantees for templates that don't require the unsafe flag. An attacker with local access can leverage this to access sensitive files through a malicious or compromised template. Public exploit code exists for this vulnerability.
Copier CLI and library versions 9.5.0 through 9.16.0 expose a trust-prefix bypass that permits unsafe template features from untrusted repositories to execute on a victim's system after user interaction. The vulnerability arises because Copier's trusted-repository prefix check evaluates the raw percent-encoded URL string, while the underlying HTTP or Git transport subsequently decodes it - meaning a URL containing encoded dot-dot segments (e.g., %2e%2e) or encoded separators (%2f, %5c) can appear to match a trusted prefix while actually resolving to an entirely different, attacker-controlled repository. No active exploitation has been confirmed (not in CISA KEV) and no public exploit code was identified in the provided data; the issue is patched in v9.17.0.
Trust-boundary bypass in Copier 9.5.0 through 9.15.1 lets an attacker-controlled template execute arbitrary commands without the usual --trust confirmation. The flaw stems from the trust prefix check using a raw str.startswith on the un-normalized template URL, so a reference that textually begins with a trusted prefix but contains '..' is granted trust while actually resolving to a different template whose tasks/migrations/jinja_extensions then run. No public exploit identified at time of analysis, and it is not in CISA KEV; fixed in 9.15.2.
Copier versions prior to 9.11.2 allow local attackers to write arbitrary files outside the intended project destination directory by exploiting symlink handling combined with the _preserve_symlinks feature in ostensibly safe templates. A malicious template author can craft a project template that bypasses security controls without requiring unsafe flags, enabling arbitrary file overwrites within the user's write permissions. Public exploit code exists for this vulnerability.
Copier versions before 9.11.2 allow local attackers to read arbitrary files outside the template directory by exploiting symlink handling when the default `_preserve_symlinks: false` setting is enabled, bypassing the library's safety guarantees for templates that don't require the unsafe flag. An attacker with local access can leverage this to access sensitive files through a malicious or compromised template. Public exploit code exists for this vulnerability.