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.
CVE-2026-27641
CRITICALPre-NVD 9.89.8Trending — 3 sources updated this week
EchelonGraph scoreLOW confidence
This critical-severity CVE scores 9.8 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
Triggered by: NVD CVSS baseline
Sources: secondary
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 9.8Exploit: None knownExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 9.8
- EG Score
- 9.8(low)
- EG Risk
- 49(Track)EG Risk 49/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity98% × 45%Exploitation0% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 1%
- EPSS %ILE
- 61%
- KEV
- Not listed
Published
February 25, 2026
Last Modified
June 17, 2026
Advisory Details (3)
Auto-updated Jul 27, 2026Patch available. Sources: github_commit, github_pr, github.
github Patch Available
Critical RCE in Flask-Reuploaded · Advisory · jugmac00/flask-reuploaded · GitHub
Affected: version 1.5.0
https://github.com/jugmac00/flask-reuploaded/security/advisories/GHSA-65mp-fq8v-56jrgithub_pr
Security/fix path traversal CVE pending
Fix merged in jugmac00/flask-reuploaded PR #180 on 2026-02-21 — awaiting tagged release
https://github.com/jugmac00/flask-reuploaded/pull/180github_commit
commit d64c6b2f71cb (jugmac00/flask-reuploaded)
Fix landed in jugmac00/flask-reuploaded commit d64c6b2f71cb — awaiting tagged release
https://github.com/jugmac00/flask-reuploaded/commit/d64c6b2f71cb73734fc38baa0e3e156926361288Affected Packages
(1 across 1 ecosystem)
PyPI(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| flask-reuploaded | 0.3 ... 1.4.0 (10 versions) | 1.5.0 | — |
Weakness Classification(2)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 6× in last 7d / 6× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-08-01 04:16 UTCEPSS rescore
- 2026-07-30 16:27 UTCEPSS rescore
- 2026-07-30 01:30 UTCEPSS rescore
- 2026-07-28 15:36 UTCEPSS rescore
- 2026-07-27 14:07 UTCEG score recompute
- 2026-07-27 13:57 UTCOSV refresh
Related CVEs(same CWE)
Frequently asked(5)
What is CVE-2026-27641?
CVE-2026-27641 is a critical vulnerability published on February 25, 2026. 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…
When was CVE-2026-27641 disclosed?
CVE-2026-27641 was first published in the National Vulnerability Database on February 25, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-27641 actively exploited?
CVE-2026-27641 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 39.2% of all scored CVEs.
What is the CVSS score of CVE-2026-27641?
CVE-2026-27641 has a CVSS v3 base score of 9.8 (NVD). The EG score is currently aggregating — additional source signals are being incorporated as they become available..
How do I remediate CVE-2026-27641?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-27641, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-27641
Is Your Infrastructure Affected by CVE-2026-27641?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.