CVE-2026-77814
is_path_trusted in scripts/iib/api.py compares the requested path against each allowed parent directory with path.startswith(parent_path), without appending a path separator.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.50%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
is_path_trusted in scripts/iib/api.py compares the requested path against each allowed parent directory with path.startswith(parent_path), without appending a path separator. A directory whose name merely begins with an allowed path therefore satisfies the comparison, so where /data/images is allowed a request for /data/images_private/secret.txt is treated as trusted and served by FileResponse, disclosing files the confinement was meant to exclude. Whether the check applies depends on get_enable_access_control in scripts/iib/tool.py: it returns true when IIB_ACCESS_CONTROL is set to enable, false when set to disable, and otherwise true when the host Stable Diffusion WebUI was started with share, ngrok, listen or server_name, falling back to false. Confinement is therefore active in the network-exposed WebUI deployments that rely on it, while a standalone run with no such option serves every readable file regardless of this flaw. The fix compares against parent_path joined with os.sep.
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.50% probability · 43th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-22
- Source
- disclosure@vulncheck.com
EPSS 0.5% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/zanllp/infinite-image-browsing
- https://github.com/zanllp/infinite-image-browsing/blob/v1.8.0/scripts/iib/api.py#L329-L344
- https://github.com/zanllp/infinite-image-browsing/commit/4057a624c7a23a36f0b4dc6a545b40767d602450
- https://github.com/zanllp/infinite-image-browsing/issues/968
- https://github.com/zanllp/infinite-image-browsing/pull/969
- https://www.vulncheck.com/advisories/infinite-image-browsing-is-path-trusted-prefix-comparison-omits-the-trailing-path-separator
- https://github.com/zanllp/infinite-image-browsing/issues/968
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.