# Craft CMS stores arbitrary content provided by unauthenticated users in session files Advisory record · `GHSA-7vrx-9684-xrf2` - **Identifiers:** `GHSA-7vrx-9684-xrf2` · `CVE-2025-35939` · `PKSA-ht16-h36v-hxc7` - **State:** Confirmed - **Severity:** CVSS 6.9 Medium - **Critical:** Yes: KEV - **Weakness (CWE):** [CWE-472](https://cwe.mitre.org/data/definitions/472.html) - **Tags:** [CWE-472](https://agentprime.io/advisories/tag/cwe-472.md) - **Published:** 8 May 2025 - **Updated:** 22 Oct 2025 - **Reviewed by a person:** No Published by the GitHub Advisory Database at 8 May 2025, 00:31 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. ## Critical Critical, because: - In CISA’s KEV catalogue since 2 Jun 2025: it is known to be exploited. How we decide what’s critical: ## Affected packages - `craftcms/cms` (Packagist): affected `>=5.0.0-alpha.1, <5.7.5 || <4.15.3`; fixed in `5.7.5`, `4.15.3` ## Machine-written summary Summary written by Claude Haiku from the source advisory. Not reviewed by a person. > Craft CMS versions before 4.15.3 and from 5.0.0-alpha.1 before 5.7.5 are affected. An unauthenticated attacker can make the site store arbitrary content, such as PHP code, in a session file on the server through the return URL parameter on login redirects, and the source says this content could be executed if combined with another vulnerability. Upgrade craftcms/cms to 4.15.3 or 5.7.5. Written 3 Nov 2026. ## Not analysed yet We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check. ## Severity and exploitation - 6.9 Medium, CVSS 4.0: `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N`, from CNA (cisa-cg) - **CISA KEV:** Listed since 2 Jun 2025: known to be exploited. - **EPSS:** 0.013, the 71st percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days. ## Timeline - 31 Oct 2026, 14:26 UTC: First seen by agentprime - 31 Oct 2026, 14:26 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-7vrx-9684-xrf2) ## Sources - [GitHub Advisory Database: GHSA-7vrx-9684-xrf2](https://github.com/advisories/GHSA-7vrx-9684-xrf2) - [OSV: GHSA-7vrx-9684-xrf2](https://osv.dev/vulnerability/GHSA-7vrx-9684-xrf2) - - - - - - - - - Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code. ## Check whether this affects you A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet. - With the agentprime MCP server (), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: - In a browser: reads your lockfile in the browser, never uploading it. - Whether it touches your code, with file and line: the Claude Code plugin, - As JSON: , or `POST https://api.agentprime.io/v1/match` with your packages () --- The web page: . Everything for agents: .