# CVE-2026-19875: IBM Langflow OSS authentication bypass in registration endpoint

Source: https://junglewise.ai/threats/cve-2026-19875-ibm-langflow-oss-authentication-bypass-in-registration-endpoint  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-19. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-19875 · Severity: high · CVSS 7.5 · Published 2026-08-19

IBM Langflow OSS is an open-source platform for building and managing AI language workflows. A missing authentication check on the user registration endpoint allows attackers to overwrite the administrator's email address and gain unauthorized control of the server, potentially using it to send phishing emails or spam.

Technologies: [Apple macOS](https://junglewise.ai/threats/technologies/macos), [IBM Langflow OSS](https://junglewise.ai/threats/technologies/langflow-oss), [Langflow](https://junglewise.ai/threats/technologies/langflow), [Linux Kernel](https://junglewise.ai/threats/technologies/kernel), [Microsoft Windows](https://junglewise.ai/threats/technologies/windows). Vendors: [Apple](https://junglewise.ai/threats/vendors/apple), [IBM](https://junglewise.ai/threats/vendors/ibm), [Langflow](https://junglewise.ai/threats/vendors/langflow), [Linux](https://junglewise.ai/threats/vendors/linux), [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-19875 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-19875 being exploited in the wild.

**How severe is CVE-2026-19875?** High severity, with a CVSS score of 7.5, published 19 August 2026.

**Which products and versions are affected?** IBM Langflow OSS 1.0.0 through 1.10.0.

**Is there a fix for CVE-2026-19875?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-19875 attacked?** It is in a software library.

**Am I affected by CVE-2026-19875?** Check whether you run Apple macOS, IBM Langflow OSS, Langflow or one of the others listed 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.

## Technical details

The vulnerability is an authentication bypass in the registration endpoint of IBM Langflow OSS versions 1.0.0 through 1.10.0. The registration function fails to validate that the user attempting to modify administrator credentials is actually authorized, allowing unauthenticated remote attackers to overwrite the admin email address. This enables account takeover and abuse of the server as an outbound mail relay. The attack requires only network access to the registration endpoint and no user interaction. A patch or update to a patched version is recommended.

## Affected products

- IBM Langflow OSS 1.0.0 through 1.10.0

## Timeline

- 2026-08-19: disclosed

## References

- [https://www.ibm.com/support/pages/node/7283810](https://www.ibm.com/support/pages/node/7283810)

## Related threats

- [Linux IOMMU page table logic error in arm_lpae_split_blk_unmap](https://junglewise.ai/threats/cve-2026-56934-in-arm-lpae-split-blk-unmap-of-drivers-iommu-io-pgtable-arm)
- [Linux kernel null pointer dereference in TCP established lookup](https://junglewise.ai/threats/cve-2026-99288-in-the-linux-kernel-the-following-vulnerability-has-been-resolved)
- [Linux kernel xen-netback race condition in XenBus disconnect](https://junglewise.ai/threats/cve-2026-99286-in-the-linux-kernel-the-following-vulnerability-has-been-resolved)
- [Windows BitLocker heap buffer overflow with physical attack](https://junglewise.ai/threats/cve-2026-97015-heap-based-buffer-overflow-in-windows-bitlocker-allows-an)
- [Microsoft Windows Shell type confusion privilege elevation](https://junglewise.ai/threats/cve-2026-97013-access-of-resource-using-incompatible-type-type-confusion-in)