Cyber Resilience

CVE-2023-49438

MediumPublic PoC

Published: 26 December 2023

Published
26 December 2023
Modified
04 November 2025
KEV Added
Patch
CVSS Score v3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS Score 0.1407 94.5th percentile
Risk Priority 21 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-49438 is a medium-severity Open Redirect (CWE-601) vulnerability in Flask-Security-Too Project Flask-Security-Too. Its CVSS base score is 6.1 (Medium).

Operationally, ranked in the top 5.5% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Deeper analysis

CVE-2023-49438 is an open redirect vulnerability affecting the Flask-Security-Too Python package at version 5.3.2 and earlier. The flaw resides in the handling of the next query parameter on the /login and /register routes, enabling redirection to arbitrary destinations.

An unauthenticated attacker can exploit the issue by supplying a crafted URL containing a malicious next parameter value. Successful abuse redirects a victim user who follows the link to an attacker-controlled site, which may be leveraged for phishing or further social-engineering attacks.

Public references include the upstream Flask-Security repository, a dedicated proof-of-concept repository, and a Fedora package-announce mailing-list posting; these sources constitute the primary locations for any subsequent patch or advisory information.

The associated EPSS score stands at 0.1407 with an identical recorded peak, indicating no material post-disclosure increase in observed exploitation interest.

EU & UK References

Vulnerability details

An open redirect vulnerability in the python package Flask-Security-Too <=5.3.2 allows attackers to redirect unsuspecting users to malicious sites via a crafted URL by abusing the ?next parameter on the /login and /register routes.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

flask-security-too project
flask-security-too
≤ 5.3.2

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-601

Security awareness includes verifying URLs and avoiding untrusted redirects that lead to malicious sites.

addresses: CWE-601

Validates redirect targets and URLs to ensure they conform to allowed destinations.

References