Security readout for executives and security teams
Plain-English summary
Copier versions before 9.11.2 can treat a supposedly safe project template as safe while allowing it to read files outside the template directory through symlinks. This matters when developers generate projects from templates they do not fully control. The issue is patched in 9.11.2.
Executive priority
Treat as a focused developer-supply-chain issue. Prioritize teams using Copier with external templates or automated project generation. Update is straightforward and should be scheduled promptly, but current public evidence does not support emergency incident response.
Technical view
CVE-2026-23968 affects copier-org Copier before 9.11.2. With the default `_preserve_symlinks: false`, a safe template can use symlinks to include arbitrary files or directories outside the local template clone. The CVE maps to CWE-61 and has CVSS 4.0 score 6.8 with user interaction required.
Likely exposure
Exposure is mainly developer workstations, build environments, or automation that run Copier against third-party or untrusted templates using versions below 9.11.2. Systems only using trusted templates have lower practical risk, but should still update.
Exploitation context
The public sources do not report active exploitation, and the CVE is not marked KEV. Exploitation requires a user or process to generate from a crafted template. The impact described is confidentiality loss through filesystem reads, not code execution.
Researcher notes
The key security boundary failure is that Copier’s safe-template model did not prevent symlink-based reads outside the template clone when symlinks were not preserved. The provided commit and advisory are the primary sources for patch details; no broader exploit telemetry is provided.
Mitigation direction
- Upgrade Copier to version 9.11.2 or later.
- Avoid running Copier against untrusted templates until upgraded.
- Review vendor advisory for any additional operational guidance.
- Restrict template sources used in developer and CI workflows.
Validation and detection
- Inventory installed Copier versions in developer and CI environments.
- Confirm affected installations are below 9.11.2.
- Identify workflows that consume third-party Copier templates.
- Check whether `_preserve_symlinks` defaults are relied on in templates.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-61: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-23968 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.8 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N——Primary CVE scoreVulnerability scoring details
Base CVSS 4.0 score
6.8MediumVector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/copier-org/copier/security/advisories/GHSA-xjhm-gp88-8pfxCVE reference · x_refsource_CONFIRM
- https://github.com/copier-org/copier/commit/b3a7b3772d17cf0e7a4481978188c9f536c8d8f6CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
UNIX Symbolic Link (Symlink) Following
UNIX Symbolic Link (Symlink) Following represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.