CVE-2026-71553
ApostropheCMS: 2nd-order prototype pollution via PATCH leading to single-request persistent DoS
ApostropheCMS is an open-source Node.js content management system. In 4.32.0 and earlier, PATCH /api/v1/article/:id accepts the inherited path toString.call and passes it through the utility module to apos.util.set() and apos.util.get(), allowing an authenticated editor to overwrite the shared Object.prototype.toString function's call property and cause a persistent process-wide denial of service until restart.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
ApostropheCMS: 2nd-order prototype pollution via PATCH leading to single-request persistent DoS
ApostropheCMS is an open-source Node.js content management system. In 4.32.0 and earlier, PATCH /api/v1/article/:id accepts the inherited path toString.call and passes it through the utility module to apos.util.set() and apos.util.get(), allowing an authenticated editor to overwrite the shared Object.prototype.toString function's call property and cause a persistent process-wide denial of service until restart.
- Record
CVE-2026-71553- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-1321
- Updated
- 2026-11-02
EUVDEUVD-2026-60442
ApostropheCMS is an open-source Node.js content management system. In 4.32.0 and earlier, PATCH /api/v1/article/:id accepts the inherited path toString.call and passes it through the utility module to apos.util.set() and apos.util.get(), allowing an authenticated editor to overwrite the shared Object.prototype.toString function's call property and cause a persistent process-wide denial of service until restart.
- Record
EUVD-2026-60442- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-vmg4-6gfg-83qx
ApostropheCMS: 2nd-order prototype pollution via PATCH leading to single-request persistent DoS
The vulnerability is a single-request persistent DoS by submitting e.g. "PATCH /api/v1/article/<id>" with a valid editor session and body of {"toString.call":"x"}, overwriting the global toString function with value x.
Fabian
- Record
GHSA-vmg4-6gfg-83qx- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-1321
- Updated
- 2026-11-02
NVD
ApostropheCMS is an open-source Node.js content management system. In 4.32.0 and earlier, PATCH /api/v1/article/:id accepts the inherited path toString.call and passes it through the utility module to apos.util.set() and apos.util.get(), allowing an authenticated editor to overwrite the shared Object.prototype.toString function's call property and cause a persistent process-wide denial of service until restart.
- Record
CVE-2026-71553- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/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 - Weakness
- CWE-1321
- Updated
- 2026-11-02
OSV
ApostropheCMS: 2nd-order prototype pollution via PATCH leading to single-request persistent DoS
ApostropheCMS is an open-source Node.js content management system. In 4.32.0 and earlier, PATCH /api/v1/article/:id accepts the inherited path toString.call and passes it through the utility module to apos.util.set() and apos.util.get(), allowing an authenticated editor to overwrite the shared Object.prototype.toString function's call property and cause a persistent process-wide denial of service until restart.
- Record
CVE-2026-71553- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-1321
- Updated
- 2026-11-02
OSVGHSA-vmg4-6gfg-83qx
ApostropheCMS: 2nd-order prototype pollution via PATCH leading to single-request persistent DoS
The vulnerability is a single-request persistent DoS by submitting e.g. "PATCH /api/v1/article/<id>" with a valid editor session and body of {"toString.call":"x"}, overwriting the global toString function with value x.
Fabian
- Record
GHSA-vmg4-6gfg-83qx- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-1321
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
apostrophenpm |
through 4.32.0 | 4.32.1 |
apostrophenpm |
before 4.32.1 | 4.32.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-71553 is a high vulnerability (CVSS 7.1) in Apostrophecms Apostrophe, published August 17, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.43%, the 37th percentile. Fixed in apostrophe 4.32.1.
References
github.com/apostrophecms/apostrophe/security/advisories/GHSA-vmg4-6gfg-83qx
nvd.nist.gov/vuln/detail/CVE-2026-71553