CVE-2026-3087

shutil.unpack_archive() doesn't check for Windows absolute paths in ZIPs

Description

If `shutil.unpack_archive()` is given a ZIP archive with an absolute Windows path containing a drive (`C:\\...`) then the archive will be extracted outside the target directory which is different than other operating systems. Only Windows is affected by this vulnerability.

Scores

Weaknesses (CWE)

• CWE-22

European references

• ENISA EUVD · EUVD-2026-25922
• GCVE · GCVE-0-2026-3087

CERT-FR advisories

• CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
• CERTFR-2026-AVI-0505 — Vulnérabilité dans Python · cert.ssi.gouv.fr

Affected configurations (NVD CPE)

• cpe:2.3:a:python:python:*:*:*:*:*:*:*:* ≤ 3.14.4
• cpe:2.3:a:python:python:3.15.0:alpha1:*:*:*:*:*:*
• cpe:2.3:a:python:python:3.15.0:alpha2:*:*:*:*:*:*
• cpe:2.3:a:python:python:3.15.0:alpha3:*:*:*:*:*:*
• cpe:2.3:a:python:python:3.15.0:alpha4:*:*:*:*:*:*
• cpe:2.3:a:python:python:3.15.0:alpha5:*:*:*:*:*:*
• cpe:2.3:a:python:python:3.15.0:alpha6:*:*:*:*:*:*
• cpe:2.3:a:python:python:3.15.0:alpha7:*:*:*:*:*:*
• cpe:2.3:a:python:python:3.15.0:alpha8:*:*:*:*:*:*

Affected products

References

• https://github.com/python/cpython/pull/146591
• https://github.com/python/cpython/issues/146581
• https://mail.python.org/archives/list/security-announce@python.org/thread/X6FXE5C6KDKOVNX3EC3DWD5RUPFWOZA4/
• https://github.com/python/cpython/commit/ab5ef98af693bded74a738570e81ea70abef2840
• https://github.com/python/cpython/commit/b01e594fbe754a960212f908d047294e880b52fd
• https://github.com/python/cpython/commit/fc829e88753858c8ac669594bf0093f44948c0f4
• https://github.com/python/cpython/commit/65b255416ae217bf0e22085be3c1976cea18bd8c
• https://github.com/python/cpython/commit/8e13025747e1ca72e86d1f35637123f9c306f0cb
• https://github.com/python/cpython/commit/8ee6aff14054b37b53e47194a2fa313e98163c94
• https://github.com/python/cpython/commit/ba0aca3bffce431fe2fbd53ca4cd6a717a2e2c19
• https://github.com/python/cpython/commit/a6650a2cdf0c49fb8ce0c982903aa2aa274beefe
• https://github.com/python/cpython/commit/7ef7dd0a74f47facd1fadcbc77f8fb03beb5eb4d
• https://github.com/python/cpython/commit/1071290169f85c09cf767c1099564a9426cdc7e8
• http://www.openwall.com/lists/oss-security/2026/04/28/9

Sources