ApostropheCMS leaves rejected CSV uploads in temporary directory
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-400.
Summary
ApostropheCMS before 4.33.0 is affected. Its unauthenticated Rich Text CSV conversion route saves each multipart upload to the system temporary directory before checking the file extension, and it does not delete the file when that check rejects it (CWE-459). A remote attacker without credentials can send repeated large rejected uploads to fill the temporary disk, which can disrupt ApostropheCMS and other services on the same partition.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
ApostropheCMS is an open-source Node.js content management system. Prior to 4.33.0, the unauthenticated Rich Text CSV conversion route writes a multipart upload to the system temporary directory before checking its extension and does not remove the staged file when that validation rejects it. Repeated large rejected uploads, using the normal public CSRF cookie, can persistently consume temporary-disk capacity and may disrupt ApostropheCMS and other services that depend on the same partition. This issue is fixed in version 4.33.0.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| apostrophecms | apostrophe | before 4.33.0 | 4.33.0 | Patch available | CNA |
| — | apostrophe (npm) | before 4.33.0 | 4.33.0 | Patch available | GHSA-qhcq-9pm2-c9w9 |
- apostrophe Vendorapostrophecms Affected before 4.33.0 Fixed in 4.33.0 Patch available CNA
- apostrophe (npm) Vendor— Affected before 4.33.0 Fixed in 4.33.0 Patch available GHSA-qhcq-9pm2-c9w9
CPE names Threatist (inferred) · 1
Inferred from how NVD named this product before; not given by a source.
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:apostrophecms:apostrophecms:*:*:*:*:*:*:*:* | — | — | apostrophecms |
- cpe:2.3:a:apostrophecms:apostrophecms:*:*:*:*:*:*:*:* Versions — — ·apostrophecms
Remediation
Upgrade ApostropheCMS (npm package apostrophe) to version 4.33.0, which fixes the issue.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
- Fix · CNA apostrophe (apostrophecms) Fixed in 4.33.0
- Fix · GHSA-qhcq-9pm2-c9w9 apostrophe (npm) Fixed in 4.33.0 Advisory →
Timeline
- 2026-10-20 Threatist record created from CVE-2026-113658
- 2026-10-21 Alias added: GHSA-qhcq-9pm2-c9w9
- 2026-10-21 Fix available: npm/[email protected] · GHSA-qhcq-9pm2-c9w9
- 2026-10-21 CVSS score added · GHSA-qhcq-9pm2-c9w9
- 2026-10-21 Weakness changed · GHSA-qhcq-9pm2-c9w9
- 2026-10-21 5 new references · GHSA-qhcq-9pm2-c9w9
- 2026-10-22 Priority changed: MEDIUM → LOW
- 2026-10-23 CISA SSVC decision points changed
- 2026-10-23 Priority changed: LOW → HIGH
References
Other 5
- https://github.com/apostrophecms/apostrophe/security/advisories/GHSA-qhcq-9pm2-c9w9
- https://github.com/apostrophecms/apostrophe/commit/9500b8b0e1d630d5e07fbb5fd2c25ed0943845ce
- https://github.com/apostrophecms/apostrophe/commit/f84fd41cbf6c22eb8d0008fc9c25df1f7130b350
- https://github.com/apostrophecms/apostrophe/releases/tag/[email protected]
- https://github.com/apostrophecms/apostrophe
More apostrophecms vulnerabilities
- TI-2026-25223 ApostropheCMS has Arbitrary File Write (Zip Slip / Path Traversal) in Import-Export Gzip Extraction CVSS 3.1CRITICAL 10.0
- TI-2026-32848 Apostrophe has default XSS via `xmp` raw-text passthrough in `sanitize-html` CVSS 3.1CRITICAL 9.3
- TI-2026-38664 @apostrophecms/seo Vulnerable to Stored XSS via Unsanitized Google Analytics / GTM ID Injected into Script Tag CVSS 3.1HIGH 8.7
- TI-2026-27673 ApostropheCMS: Stored XSS in SEO Fields Leads to Authenticated API Data Exposure in ApostropheCMS CVSS 3.1HIGH 8.7
- TI-2026-76992 Unauthenticated resource exhaustion via ApostropheCMS import routes CVSS 3.1HIGH 7.5
- TI-2026-38665 Prototype pollution in apostrophecms apostrophe CVSS 3.1CRITICAL 9.1
Sources
- CVE-2026-113658 · CVE Program
- CVE-2026-113658 · NVD
- FIRST EPSS
- GHSA-qhcq-9pm2-c9w9 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences