GHSA-c8rr-9gxc-jprv · Severity: high · Ecosystem: pip — UltraJSON has an integer overflow handling large indent leads to buffer overflow or infinite loop
UltraJSON is a fast JSON encoder and decoder written in pure C with bindings for Python 3.7+. Versions 5.10 through 5.11.0 are vulnerable to buffer overflow or infinite loop through large indent handling. ujson.dumps() crashes the Python interpreter (segmentation fault) when the product of the indent parameter and the nested depth of the input exceeds INT32_MAX. It can also get stuck in an infinite loop if the indent is a large negative number. Both are caused by an integer overflow/underflow whilst calculating how much memory to reserve for indentation. And both can be used to achieve denial of service. To be vulnerable, a service must call ujson.dump()/ujson.dumps()/ujson.encode() whilst giving untrusted users control over the indent parameter and not restrict that indentation to reasonably small non-negative values. A service may also be vulnerable to the infinite loop if it uses a fixed negative indent. An underflow always occurs for any negative indent when the input data is at least one level nested but, for small negative indents, the underflow is usually accidentally rectified by another overflow. This issue has been fixed in version 5.12.0.
Conclusion & alert: CVE-2026-32875 is rated Exploit Available (50.5/100): CVSS High severity, with low exploitation likelihood (EPSS 0.05%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-04-21 | 0.04% | 0.05% | +0.01% |
| 2 | 2026-03-20 | — | 0.04% | — |
Full EPSS history (2 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | [email protected] |
GHSA-c8rr-9gxc-jprv · Severity: high · Ecosystem: pip — UltraJSON has an integer overflow handling large indent leads to buffer overflow or infinite loop
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2026-32875 not yet assigned priority: Debian including 1 source packages (ujson), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 5. | https://security-tracker.debian.org/tracker/CVE-2026-32875 |
redhat
|
high | — | https://access.redhat.com/security/cve/CVE-2026-32875 |
ubuntu
|
medium | CVE-2026-32875 medium priority: Ubuntu including 3 source packages (collada2gltf, pandas, ujson), 24 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): not-affected 14, DNE 5, released 5. | https://ubuntu.com/security/CVE-2026-32875 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| ultrajson_project | ultrajson | >= 5.1.0, < 5.12.0 | cpe:2.3:a:ultrajson_project:ultrajson:*:*:*:*:*:python:*:* |
| URL | Tags |
|---|---|
| https://github.com/ultrajson/ultrajson/commit/486bd4553dc471a1de11613bc7347a6b318e37ea | Patch |
| https://github.com/ultrajson/ultrajson/issues/700 | Issue Tracking |
| https://github.com/ultrajson/ultrajson/security/advisories/GHSA-c8rr-9gxc-jprv | Exploit Vendor Advisory |