CVE-2026-29036
cJSON JSON Pointer parsing flaw allows silent data corruption or deletion via JSON Patch.
Is CVE-2026-29036 being exploited?
Not confirmed. CVE-2026-29036 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.26% probability of exploitation in the next 30 days.
How severe is CVE-2026-29036?
CVE-2026-29036 is rated High with a CVSS score of 8.7. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-29036?
Not known from our data. No patch reference has been recorded for CVE-2026-29036, which is not the same as no patch existing — a fix may have shipped without a tagged reference, or after this record was written. The vendor advisory is the only authority on whether a fix exists, and mitigations may be available regardless.
What does CVE-2026-29036 affect?
CVE-2026-29036 affects cJSON versions 1.5.0 - 1.7.19, cJSON_Utils.c: decode_pointer_inplace(), cJSONUtils_ApplyPatches() / ApplyPatchesCaseSensitive(), Applications using cJSON for RFC6902 JSON Patch. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-29036?
Block/validate JSON Patch input and upgrade to patched cJSON when released.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Crafted RFC6902 JSON Patch (~0/~1 escapes) can target wrong keys, causing silent data corruption or deletion and bypassing app authorization.
Immediate action required
- affected>= 1.5.0 and <= 1.7.19
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.