CVE-2026-54015 | Open WebUI: Prompt history IDOR: unbound history_id allows cross-prompt read and deletion

Exp

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.6, Open WebUI's prompt version-history endpoints authorize the prompt_id in the URL but then act on caller-supplied history IDs without verifying that the history row belongs to that prompt (history_entry.prompt_id == prompt.id). This affects /api/v1/prompts/id/{prompt_id}/history/diff, /api/v1/prompts/id/{prompt_id}/update/version, and /api/v1/prompts/id/{prompt_id}/history/{history_id}. An authenticated user with access to any prompt they control, plus a victim prompt_history.id, can read or delete another user's private prompt history. This vulnerability is fixed in 0.9.6.

Published: 2026-06-23 Last update: 2026-06-25 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-54015 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.16%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-54015

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-54015

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-24 0.04% 0.16% +0.12%
2 2026-06-12 0.04%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-54015

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
1.6 4.7 [email protected]

Weakness enumeration for CVE-2026-54015

GitHub Security Advisory for CVE-2026-54015

GHSA-4r4w-2wgp-w7cj · Severity: medium · Ecosystem: pip — Open WebUI Prompt history IDOR: unbound history_id allows cross-prompt read and deletion

Affected software / configurations for CVE-2026-54015

Vendor Product Version Raw CPE
openwebui open_webui < 0.9.6 cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*

References for CVE-2026-54015

cvelogic Threat Intelligence