# CVE-2026-124586: Tencent RapidJSON diyfp.h GetCachedPowerByIndex out-of-bounds

Status: published. Published: 2026-11-09. Updated: 2026-11-09.

A vulnerability was determined in Tencent RapidJSON 1.1.0. Impacted is the function GetCachedPowerByIndex in the library include/rapidjson/internal/diyfp.h. This manipulation of the argument decimalPosition causes out-of-bounds read. It is possible to initiate the attack remotely. The exploit has been publicly disclosed and may be utilized. The project was informed of the problem early through an issue report but has not responded yet.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Tencent / RapidJSON: 1.1.0 (affected). Source: CNA: VulDB

## Severity and prioritization

- CVSS 4.0: 6.9 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P; source: CNA: VulDB

- CVSS 3.1: 7.3 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:C; source: CNA: VulDB

- CVSS 3.0: 7.3 (high); CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:C; source: CNA: VulDB

- CVSS 2.0: 7.5 (high); AV:N/AC:L/Au:N/C:P/I:P/A:P/E:POC/RL:ND/RC:C; source: CNA: VulDB

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-125, CWE-119

## Exploit evidence

- exploit: https://github.com/Tencent/rapidjson/issues/2405 (CNA: VulDB)

## References

- https://vuldb.com/vuln/433010 (CNA: VulDB; vdb-entry, technical-description)

- https://vuldb.com/vuln/433010/cti (CNA: VulDB; signature, permissions-required)

- https://vuldb.com/cve/CVE-2026-124586 (CNA: VulDB; third-party-advisory)

- https://vuldb.com/submit/1039172 (CNA: VulDB; third-party-advisory)

- https://github.com/Tencent/rapidjson/issues/2405 (CNA: VulDB; exploit, issue-tracking)

- https://github.com/Tencent/rapidjson/ (CNA: VulDB; product)

## Provenance

- CNA: VulDB: https://www.cve.org/CVERecord?id=CVE-2026-124586; retrieved 2026-11-09; source updated 2026-11-09

Revision: f5cf8d5efb578a733bb498f368c9f908a73c17762deccc2d447927c8c996e89c

Canonical: https://y2.dev/cve/CVE-2026-124586

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