VulnerabilityPublished 8 Apr 2026

CVE-2026-34392: aces Loris · Exposed Files or Directories

Affects aces LorisSource CVE Database V5

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Not known to be exploited · CVSS 7.5 High : upgrade to 28.0.1 or 27.0.3 soon.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

7.5High

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 16% 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:N/S:U/C:H/I:N/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
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: None: The vulnerable system can be exploited without any interaction from any user.
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: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
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 8 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 and aces/loris to 28.0.1 or 27.0.3.

Affected software

Product	Affected	Fixed in
acesLoris	Affected >=28.0.0 <28.0.1	Fixed in 28.0.1
acesLoris	Affected >=20.0.0 <27.0.3	Fixed in 27.0.3
GitHubaces/loris`pkg:github/aces/loris`Other threats	Affected 20.0.0 <27.0.3 28.0.0 <28.0.1	Fixed in 27.0.3 28.0.1

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. Patch status is not explicitly confirmed in the provided data; therefore, users must consult the official vendor advisory for confirmation and further guidance. No alternative mitigations or temporary fixes are indicated.

Description

LORIS, a self-hosted web application for neuroimaging research data management, contains a directory traversal vulnerability in its static file router in versions from 20.0.0 up to but not including 27.0.3, and from 28.0.0 up to but not including 28.0.1. This flaw allows attackers to access files outside the intended directories via static, css, and js endpoints.

Impact

An attacker can remotely download unintended files from the server hosting LORIS without authentication, potentially exposing sensitive data. The integrity and availability of the system are not affected. There are no known exploits in the wild at this time.

Summary

CVE-2026-34392 is a directory traversal vulnerability (CWE-552) in the static file router of the aces LORIS application versions >=20.0.0 and <27.0.3, and >=28.0.0 and <28.0.1. This bug permits attackers to traverse outside the intended directory boundaries and download arbitrary files via static, css, and js endpoints. The issue is resolved in versions 27.0.3 and 28.0.1. The vulnerability has a CVSS 3.1 base score of 7.5, reflecting network attack vector, low complexity, no privileges required, no user interaction, unchanged scope, and high confidentiality impact without integrity or availability impact.

CWE-552Files or Directories Accessible to External Parties (opens in a new tab)
Base weaknessOWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The product makes files or directories accessible to unauthorized actors, even though they should not be.
Implementation · System Configuration · Operation
When storing data in the cloud (e.g., S3 buckets, Azure blobs, Google Cloud Storage, etc.), use the provider's controls to disable public access.
OWASP Cheat Sheets
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V12.5.1 (opens in a new tab)
V12.4.1 (opens in a new tab)
V8.3.8 (opens in a new tab)
Attack patterns
Collect Data from Common Resource Locations (opens in a new tab)
Probe System Files (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

github.com/aces/Loris/security/advisories/GHSA-rfj5-58hv-wc5f (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 16 Apr 2026, 12:20 UTC

WeaknessesCWE-552

Technical details

References

Community reviews

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