VulnerabilityPublished 9 Apr 2026

CVE-2026-39985: aces Loris · Open Redirect

Affects aces LorisSource CVE Database V5

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Not known to be exploited · CVSS 4.3 Medium : upgrade to 28.0.1 or 27.0.3 when convenient.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

4.3Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 28.0.1, 27.0.3

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: Required
Scope: Unchanged
Confidentiality: Low
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 9 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 24 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade Loris to 28.0.1 or 27.0.3; aces/Loris to 27.0.3.

Affected software

Product	Affected	Fixed in
acesLoris	Affected >=28.0.0 <28.0.1	Fixed in 28.0.1
acesLoris	Affected <27.0.3	Fixed in 27.0.3
GitHubaces/Loris`pkg:github/aces/Loris`Other threats	Affected <27.0.3	Fixed in 27.0.3

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

The vulnerability is fixed in LORIS versions 27.0.3 and 28.0.1. Users should upgrade to one of these versions or later to remediate the issue. Since no official vendor advisory or patch links are provided, verify the upgrade availability from the official LORIS project sources. No additional mitigation steps are indicated by the vendor advisory.

Description

LORIS (Longitudinal Online Research and Imaging System) is a self-hosted web application that provides data- and project-management for neuroimaging research. Prior to 27.0.3 and 28.0.1, the redirect parameter upon login to LORIS was not validating the value of the redirect as being within LORIS, which could be used to trick users into visiting arbitrary URLs if they are given a link with a third party redirect parameter. This vulnerability is fixed in 27.0.3 and 28.0.1.

Impact

The vulnerability allows an attacker to craft URLs that redirect users to untrusted external sites after login, which could facilitate phishing or social engineering attacks. There is no direct impact on data confidentiality, integrity, or availability. No known exploitation in the wild has been reported.

Summary

CVE-2026-39985 is an open redirect vulnerability (CWE-601) in the LORIS web application used for neuroimaging research data management. The vulnerability arises from improper validation of the redirect parameter upon user login, which could be manipulated to redirect users to arbitrary external URLs. This could potentially be used in phishing or social engineering attacks to trick users into visiting malicious sites. The flaw affects LORIS versions before 27.0.3 and versions from 28.0.0 up to but not including 28.0.1. The issue is resolved in versions 27.0.3 and 28.0.1. The CVSS 3.1 base score is 4.3, reflecting a medium severity with network attack vector, low attack complexity, no privileges required, user interaction required, and limited confidentiality impact.

CWE-601URL Redirection to Untrusted Site (Open Redirect) (opens in a new tab)
Base weaknessLikelihood of exploit: LowOWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect.
Implementation · Input Validation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
Architecture and Design
Use an intermediate disclaimer page that provides the user with a clear warning that they are leaving the current site. Implement a long timeout before the redirect occurs, or force the user to click on the link. Be careful to avoid XSS problems (CWE-79) when generating the disclaimer page.
Architecture and Design · Enforcement by Conversion
When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
OWASP Cheat Sheets
Mass Assignment (opens in a new tab)
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V5.1.5 (opens in a new tab)
Attack patterns
Cross-Site Flashing (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 17 Apr 2026, 12:27 UTC

WeaknessesCWE-601

Technical details

References

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