# CVE-2026-3390: FascinatedBox lily Error Reporting lily_build_error.c patch_line_end out-of-bounds

> A local attacker can trigger an out-of-bounds read in the lily programming language's error reporting, potentially causing a denial of service.

- **Severity:** Medium 4.8 (`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`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 1 Mar 2026
- **Updated:** 2 Mar 2026
- **Also known as:** GHSA-grfq-fj8g-fxq5

## What is CVE-2026-3390?

CVE-2026-3390 is a medium-severity memory corruption vulnerability in FascinatedBox lily, published on 1 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability was identified in FascinatedBox lily up to 2.3. This issue affects the function patch_line_end of the file src/lily_build_error.c of the component Error Reporting. The manipulation leads to out-of-bounds read. The attack can only be performed from a local environment. The exploit is publicly available and might be used. The project was informed of the problem early through an issue report but has not responded yet.

Weakness: CWE-125 (Out-of-bounds Read), CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2026-3390?

It affects 1 product.


Products: Lily-Lang Lily.

## How do I fix CVE-2026-3390?

No fix has been published for CVE-2026-3390 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-3390 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-3390 exists.

## Other vulnerabilities in FascinatedBox lily

- [CVE-2026-3391](https://insights.sbomify.com/CVE-2026-3391/): FascinatedBox lily lily_emitter.c clear_storages out-of-bounds (medium 4.8)
- [CVE-2026-3392](https://insights.sbomify.com/CVE-2026-3392/): FascinatedBox lily lily_emitter.c eval_tree null pointer dereference (medium 4.8)
- [CVE-2026-2660](https://insights.sbomify.com/CVE-2026-2660/): FascinatedBox lily lily_symtab.c shorthash_for_name use after free (medium 4.8)
- [CVE-2026-2662](https://insights.sbomify.com/CVE-2026-2662/): FascinatedBox lily lily_emitter.c count_transforms out-of-bounds (medium 4.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-3390 and fix it if it is affected.

What it is: CVE-2026-3390 is a medium-severity memory corruption vulnerability in FascinatedBox lily, published on 1 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-3390 exists.

Affected product: FascinatedBox lily. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-3390/ (Markdown: https://insights.sbomify.com/CVE-2026-3390/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-3390
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-3390
- OSV: https://osv.dev/vulnerability/CVE-2026-3390

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-3390/
Summaries are generated and may contain mistakes; the official description above is the record.