CVE-2026-27641 json
Flask-Reuploaded vulnerable to Remote Code Execution via Server-Side Template Injection
published 2026-02-25 8 mo ago modified 2026-10-27 12 d ago also GHSA-65mp-fq8v-56jr , PYSEC-2026-341 , EUVD-2026-8616
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.3%
- EPSS 1.3% chance of exploitation in 30 days, percentile 71%
- public exploits
- 0
- none known
Summary
Flask-Reuploaded provides file uploads for Flask. A critical path traversal and extension bypass vulnerability in versions prior to 1.5.0 allows remote attackers to achieve arbitrary file write and remote code execution through Server-Side Template Injection (SSTI). Flask-Reuploaded has been patched in version 1.5.0. Some workarounds are available. Do not pass user input to the `name` parameter, use auto-generated filenames only, and implement strict input validation if `name` must be used.
Patch / fix
- pypi flask-reuploaded 1.5.0
- jugmac00 flask-reuploaded 1.5.0
- github.com/jugmac00/flask-reuploaded@d64c6b2 commit
- github.com/jugmac00/flask-reuploaded#180 pull request
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- 8 mo ago
Exploit prediction
1.34% chance of exploitation in the next 30 days, higher than 71% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/jugmac00/flask-reuploaded/security/advisories/GHSA-65mp-fq8v-56jr referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| OSV | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| GitHub | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | flask-reuploaded | <1.5.0 |
1.5.0 |
Affected products
- jugmac00 flask-reuploaded
Classification
References
-
github.com
/jugmac00/flask-reuploaded/pull/180
web, issue-tracking, patch
-
github.com
/jugmac00/flask-reuploaded/commit/d64c6b2f71cb73734fc38baa0e3e156926361288
web, patch
-
github.com
/jugmac00/flask-reuploaded/security/advisories/GHSA-65mp-fq8v-56jr
web, exploit, vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-27641
advisory
-
github.com
/jugmac00/flask-reuploaded
package
-
github.com
/pypa/advisory-database/tree/main/vulns/flask-reuploaded/PYSEC-2026-341.yaml
web
-
pypi.org
/project/flask-reuploaded
web, package
-
github.com
/advisories/GHSA-65mp-fq8v-56jr
advisory
Sources
- CVE List CVE-2026-27641
- GitHub Advisory GHSA-65mp-fq8v-56jr
- NVD CVE-2026-27641
- OSV PYSEC-2026-341
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.