What is CVE-2026-103263?

CVE-2026-103263 is a medium-severity vulnerability in Tornadoweb Tornado, classified under Improper Link Resolution Before File Access. CVSS score: 5.9/10. Published 2026-10-01.

How severe is CVE-2026-103263?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Vulnerability in Tornadoweb Tornado

CVE-2026-103263

Tornado before 6.5.9 contains a path traversal vulnerability in StaticFileHandler that follows symbolic links inside the static root without confirming the resolved target stays within it. When a symlink pointing outside the static directory exists inside it, unauthenticated attackers can request it to read files such as configuration files, private keys, and application secrets accessible to the process user.

Published 2026-10-01 · last modified 2026-10-01.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Tornadoweb Tornado

Weakness classification (CWE)

CWE-59 — Improper Link Resolution Before File Access

References

github.com/tornadoweb/tornado/security/advisories/GHSA-c2m8-h5v5-343r (vendor-advisory)
github.com/tornadoweb/tornado/commit/437ab5f76565403b3403438d2e555d11f8128d32 (patch)
www.vulncheck.com/advisories/tornado-before-6.5.9-staticfilehandler-path-traver… (third-party-advisory)

Frequently asked questions

What is CVE-2026-103263?: CVE-2026-103263 is a medium-severity vulnerability in Tornadoweb Tornado, classified under Improper Link Resolution Before File Access. CVSS score: 5.9/10. Published 2026-10-01.
How severe is CVE-2026-103263?: Medium severity. CVSS v3 base score is 5.9 out of 10.