High severity · published Jul 31, 2026
CVE-2026-62999
Copier: Percent-encoded dot segments in template URLs can allow trusted-prefix escape (Incomplete fix for trust-prefix bypass)
7.5
CVSS
0.4%
EPSS
No
On KEV
Description
Copier is a library and CLI app for rendering project templates. From 9.5.0 through 9.16.0, percent-encoded parent-directory segments or encoded path separators in a template URL can match a configured trusted repository prefix before an HTTP server or Git transport decodes the path, allowing unsafe template features from a repository outside the trusted prefix to run after user interaction. This issue is fixed in version 9.17.0.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CO
copier · copier-org
>= 9.5.0, <= 9.16.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-62999
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-62999
github.com
https://github.com/copier-org/copier/commit/7408f0d6287a7bf452715fd9f25dc54eaba3c295
github.com
https://github.com/copier-org/copier/releases/tag/v9.17.0
github.com
https://github.com/copier-org/copier/security/advisories/GHSA-34mv-rjq9-5mch
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