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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-16554 Detail

Description

cJSON library is vulnerable to an integer overflow in the print_string_ptr() function in cJSON.c on 32-bit platforms. The escape_characters counter, a 32-bit size_t, can wrap around when processing strings containing approximately 858,993,460 or more control characters, causing the output buffer to be allocated based on an underestimated length. When cJSON_PrintBuffered() is used with a pre-allocated buffer, the subsequent write loop overflows the heap allocation. An attacker supplying a crafted JSON string to an application using cJSON on a 32-bit platform can cause a heap buffer overflow, potentially leading to remote code execution, information disclosure, or denial of service. Because project creator contact attempts were unsuccessful, the vulnerability has only been confirmed in version 1.7.19 but may also affect other versions.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  CERT.PL
CVSS-B 5.1 MEDIUM
Vector:  CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:L/SI:L/SA:L

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://cert.pl/en/posts/2026/07/CVE-2026-16554 CERT.PL
https://github.com/DaveGamble/cJSON CERT.PL

Weakness Enumeration

CWE-ID CWE Name Source
CWE-190 Integer Overflow or Wraparound CERT.PL  

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-16554
NVD Published Date:
07/27/2026
NVD Last Modified:
07/27/2026
Source:
CERT.PL