CVE-2026-61486 Apache Lucy: stack-buffer-overflow in JSON parser error reporter on malformed input

Critical 9.8 Published 5 Aug 2026 Updated 4 Sep 2026

A stack buffer overflow in the JSON parser allows attackers to cause denial of service or execute code via malformed input in the retired Apache Lucy library.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-61486?

CVE-2026-61486 is a critical memory corruption vulnerability in Apache Lucy, published on 5 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

** UNSUPPORTED WHEN ASSIGNED ** Stack-based Buffer Overflow vulnerability in Apache Lucy.

This issue affects Apache Lucy: all versions.

As this project is retired, we do not plan to release a version that fixes this issue. Users are recommended to find an alternative or restrict access to the instance to trusted users.

Lucy is now maintained outside of the ASF at https://github.com/lucysearch . This issue has been fixed in 0.8.0 there.

NOTE: This vulnerability only affects products that are no longer supported by the maintainer.

Weakness: CWE-121

Which versions are affected by CVE-2026-61486?

It affects 1 product.

Products include Apache Lucy.

How do I fix CVE-2026-61486?

No fix has been published for CVE-2026-61486 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2026-61486 being exploited?

There is no known exploitation of CVE-2026-61486 in the wild and no public exploit code.

Sources

Also known as GHSA-phfr-gw5r-65ff.