# CVE-2026-29975: Denial of service in n/a

> A remote attacker can cause applications using the lwjson streaming parser to hang indefinitely by sending specific JSON strings, resulting in denial of service.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 8 May 2026
- **Updated:** 8 May 2026
- **Also known as:** GHSA-hr45-w7f7-w9j6

## What is CVE-2026-29975?

CVE-2026-29975 is a high-severity denial of service vulnerability in n/a, published on 8 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

lwjson 1.8.1 contains an improper input validation vulnerability in the streaming JSON parser (lwjson_stream.c). The end-of-string detection logic incorrectly identifies escaped quote characters by only checking the immediately preceding character rather than counting consecutive backslashes, causing valid JSON strings ending with an escaped backslash (like "\\") to never terminate parsing. A remote attacker can send well-formed JSON to cause applications using lwjson_stream_parse() to hang indefinitely, resulting in denial of service.

Weakness: CWE-835 (Loop with Unreachable Exit Condition)

## Which versions are affected by CVE-2026-29975?


## How do I fix CVE-2026-29975?

No fix has been published for CVE-2026-29975 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-29975 being exploited?

There is no known exploitation of CVE-2026-29975 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-29975 and fix it if it is affected.

What it is: CVE-2026-29975 is a high-severity denial of service vulnerability in n/a, published on 8 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-29975 in the wild and no public exploit code.

Affected product: n/a. 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-2026-29975/ (Markdown: https://insights.sbomify.com/CVE-2026-29975/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-29975
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-29975
- OSV: https://osv.dev/vulnerability/CVE-2026-29975

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-29975/
Summaries are generated and may contain mistakes; the official description above is the record.