CVE-2026-23835: lobehub lobe-chat · External Control of File Name or Path
Affects lobehub lobe-chatSource CVE Database V5
Public exploit available · CVSS 5.7 Medium : upgrade to 1.143.3 as a priority.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 30% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.143.3
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:PExploitation evidence
Disclosed: evidence found.
CVE published 30 Jan 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: evidence found.
CVSS exploit maturity: proof of concept public
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), CVSS vector, the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade lobe-chat and lobehub/lobe-chat to 1.143.3.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| lobehublobe-chat | Affected
| Fixed in
|
GitHublobehub/lobe-chatpkg:github/lobehub/lobe-chatOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
European organizations should immediately upgrade lobe-chat to version 1.143.3 or later to apply the official patch. Beyond patching, implement strict validation and sanitization of all file upload parameters on the server side to prevent tampering. Employ robust access controls to restrict upload capabilities to trusted users and monitor upload activities for anomalies such as unusual file paths or size discrepancies. Integrate quota enforcement mechanisms that rely on server-side calculations rather than client-supplied data to prevent quota bypass. Deploy file integrity monitoring and alerting systems to detect unauthorized file creations or modifications. Regularly audit storage usage and backup processes to identify abnormal consumption patterns. Consider isolating upload directories with strict permissions and sandboxing to limit the impact of arbitrary file writes. Enhance logging and monitoring of upload-related events to facilitate rapid detection and response. Finally, educate users and administrators about the risks of manipulating upload parameters and encourage prompt reporting of suspicious behavior.
Description
LobeHub is an open source human-and-AI-agent network. Prior to version 1.143.3, the file upload feature in `Knowledge Base > File Upload` does not validate the integrity of the upload request, allowing users to intercept and modify the request parameters. As a result, it is possible to create arbitrary files in abnormal or unintended paths. In addition, since `lobechat.com` relies on the size parameter from the request to calculate file usage, an attacker can manipulate this value to misrepresent the actual file size, such as uploading a `1 GB` file while reporting it as `10 MB`, or falsely declaring a `10 MB` file as a `1 GB` file. By manipulating the size value provided in the client upload request, it is possible to bypass the monthly upload quota enforced by the server and continuously upload files beyond the intended storage and traffic limits. This abuse can result in a discrepancy between actual resource consumption and billing calculations, causing direct financial impact to the service operator. Additionally, exhaustion of storage or related resources may lead to degraded service availability, including failed uploads, delayed content delivery, or temporary suspension of upload functionality for legitimate users. A single malicious user can also negatively affect other users or projects sharing the same subscription plan, effectively causing an indirect denial of service (DoS). Furthermore, excessive and unaccounted-for uploads can distort monitoring metrics and overload downstream systems such as backup processes, malware scanning, and media processing pipelines, ultimately undermining overall operational stability and service reliability. Version 1.143.3 contains a patch for the issue.