CVE-2025-35939
Craft CMS stores user-provided content in session files
Exploited in the wild. In CISA KEV since 2025‑06‑02. Fixed versions are out.
What to do
Find your product and version, then upgrade to the build on the right.
- Craft CMSAffected: < 5.7.5Upgrade to: 5.7.5Affected: < 4.15.3Upgrade to: 4.15.3Stated by: CVE record
- Packagist craftcms/cmsAffected: ≥ 5.0.0-alpha.1, < 5.7.5Upgrade to: 5.7.5Stated by: GitHub advisory
- Craftcms Craft CmsAffected: < 4.15.3Upgrade to: 4.15.3Stated by: NVD
- Crafter Software Corporation Crafter CMSAffected: до 5.7.5Upgrade to: not statedStated by: BDU
Versions as the sources state them. Full version matrix after sign-in
Coverage timeline
0 publishersAdded to CISA KEV catalog
Sourced from public security reporting — each date is when it was published, not when it happened.
What it is
From the CVE record
Craft CMS stores arbitrary content provided by unauthenticated users in session files. This content could be accessed and executed, possibly using an independent vulnerability. Craft CMS redirects requests that require authentication to the login page and generates a session file on the server at '/var/lib/php/sessions'. Such session files are named 'sess_[session_value]', where '[session_value]' is provided to the client in a 'Set-Cookie' response header. Craft CMS stores the return URL requested by the client without sanitizing parameters. Consequently, an unauthenticated client can introduce arbitrary values, such as PHP code, to a known local file location on the server. Craft CMS versions 5.7.5 and 4.15.3 have been released to address this issue.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Listed as exploited in the wild since 2025-06-02.
US federal agencies must remediate by 2025-06-23.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
1.3% chance of exploitation activity in the next 30 days, which ranks it in the 71st percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
- Attention now
Sustained.
Lifecycle
6 events over 411 days, from the signal feeds we watch.
- EPSS band changemoderate → low
- Patch availablerecord updated
- Added to CISA KEV
- Publishedweakness classified
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Scored 5.3 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- Integrity LowData modification is possible but limited in scope or consequence
- Availability NoneNo availability impact
Weaknesses
Sources
References in the record
- github.com/craftcms/cms/pull/17220
- github.com/craftcms/cms/releases/tag/4.15.3
- github.com/craftcms/cms/releases/tag/5.7.5
And 7 more references. See all after sign-in
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