CVE-2026-42259: Saltcorn is an extensible, open source, no-code database application builder. Prior to versions 1.4.6, 1.5.6, and 1.6.0-beta.5, Saltcorn validates the...

Description

Saltcorn is an extensible, open source, no-code database application builder. Prior to versions 1.4.6, 1.5.6, and 1.6.0-beta.5, Saltcorn validates the post-login dest parameter with a string check that only blocks :/ and //. Because all WHATWG-compliant browsers normalise backslashes (\) to forward slashes (/) for special schemes, a payload such as /\evil.com/path slips through is_relative_url(), is emitted unchanged in the HTTP Location header, and causes the browser to navigate cross-origin to an attacker-controlled domain. The bug is reachable on a default install and only requires a victim who can be tricked into logging in via a crafted Saltcorn URL. This issue has been patched in versions 1.4.6, 1.5.6, and 1.6.0-beta.5.

Metrics

CVSS 4.0

5.1/10

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Probability

0.34%

25.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-601

References

Timeline

Published: May 7, 2026
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2026-42259?

Saltcorn is an extensible, open source, no-code database application builder. Prior to versions 1.4.6, 1.5.6, and 1.6.0-beta.5, Saltcorn validates the post-login dest parameter with a string check that only blocks :/ and //. Because all WHATWG-compliant browsers normalise backslashes (\) to forward slashes (/) for special schemes, a payload such as /\evil.com/path slips through is_relative_url(), is emitted unchanged in the HTTP Location header, and causes the browser to navigate cross-origin to an attacker-controlled domain. The bug is reachable on a default install and only requires a victim who can be tricked into logging in via a crafted Saltcorn URL. This issue has been patched in versions 1.4.6, 1.5.6, and 1.6.0-beta.5.

How severe is CVE-2026-42259?

CVE-2026-42259 has a CVSS score of 5.1/10 (MEDIUM severity). The EPSS model estimates a 0.34% probability of exploitation in the next 30 days.

How do I fix CVE-2026-42259?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.