CVE-2026-111987: AUTOMATIC1111 stable-diffusion-webui stored XSS in Extra-Networks Card Builder

CVE-2026-111987 · Severity: medium · CVSS 4.3 · Published 2026-10-18

AUTOMATIC1111's Stable Diffusion web UI is a popular tool for generating AI-based images that processes model metadata when displaying extra-network cards. The vulnerability allows attackers to inject malicious code into model metadata (specifically the sshs_model_hash field in safetensors files), which executes in the browser when viewed by users. An attacker could redirect users to malicious websites, steal authentication tokens, or escalate to remote code execution through the extension installer.

Technologies: AUTOMATIC1111 Stable Diffusion WebUI. Vendors: AUTOMATIC1111.

Quick answers

Is CVE-2026-111987 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-111987 being exploited in the wild.
How severe is CVE-2026-111987?
Medium severity, with a CVSS score of 4.3, published 18 October 2026.
Which products and versions are affected?
AUTOMATIC1111 Stable Diffusion WebUI up to 1.10.1.
Is there a fix for CVE-2026-111987?
Yes: fixed in <UNKNOWN>. Until then: <UNKNOWN> Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-111987 attacked?
It is attacked over the network.
Am I affected by CVE-2026-111987?
Check whether you run AUTOMATIC1111 Stable Diffusion WebUI at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • Fixed in: <UNKNOWN>

<UNKNOWN>

Technical details

Stored cross-site scripting in the read_metadata_from_safetensors function within modules/sd_models.py of the Extra-Networks Card Builder component. The vulnerability arises from insufficient sanitization of the __metadata__.sshs_model_hash field when displaying model cards, allowing attackers to inject JavaScript that executes in the context of the web UI. The attack can be triggered remotely by distributing malicious safetensors model files and requires no authentication; the vulnerability is further exploitable for remote code execution through the extension installer mechanism.

Affected products

  • AUTOMATIC1111 stable-diffusion-webui up to 1.10.1

Timeline

  • 2026-10-18: disclosed
  • other: Exploit is publicly available

References

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