# CVE-2026-31988: yauzl 3.2.0 - Denial of Service via Off-by-One Error in NTFS Timestamp Parser

> A remote attacker can crash Node.js applications processing zip files by sending a crafted archive with a malformed NTFS timestamp field.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 11 Mar 2026
- **Updated:** 12 Mar 2026
- **Also known as:** ECHO-8347-6a0d-51d6, GHSA-gmq8-994r-jv83, MINI-22cx-g8jr-7fg7, MINI-2m86-62mx-874f, MINI-5ff9-68hf-p3v7, MINI-696q-7r8m-2793, MINI-7m3g-cw6r-j84q, MINI-959q-mg2x-hgx7, MINI-g58w-gxp2-g28r, MINI-hqvw-7cqr-mvhg, MINI-mq46-mwqx-pmh7, MINI-mrw8-gc3f-9gcg, MINI-rv7p-xccc-fj8f, MINI-w4g8-9hw3-rmqm, MINI-wjc5-6hv7-4883, ROOT-APP-NPM-CVE-2026-31988, UBUNTU-CVE-2026-31988

## What is CVE-2026-31988?

CVE-2026-31988 is a medium-severity denial of service vulnerability in thejoshwolfe yauzl, published on 11 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

yauzl (aka Yet Another Unzip Library) version 3.2.0 for Node.js contains an off-by-one error in the NTFS extended timestamp extra field parser within the getLastModDate() function. The while loop condition checks cursor < data.length + 4 instead of cursor + 4 <= data.length, allowing readUInt16LE() to read past the buffer boundary. A remote attacker can cause a denial of service (process crash via ERR_OUT_OF_RANGE exception) by sending a crafted zip file with a malformed NTFS extra field. This affects any Node.js application that processes zip file uploads and calls entry.getLastModDate() on parsed entries. Fixed in version 3.2.1.

Weakness: CWE-193 (Off-by-one Error)

## Which versions are affected by CVE-2026-31988?

2 open source packages ship an affected version, including yauzl.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `yauzl` | npm | From 3.2.0 | 3.2.1 |
| `yauzl` | npm | From 3.2.0 | 3.2.1 |

## How do I fix CVE-2026-31988?

Upgrade yauzl to 3.2.1 or later.

## Is CVE-2026-31988 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-31988 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-31988 and fix it if it is affected.

What it is: CVE-2026-31988 is a medium-severity denial of service vulnerability in thejoshwolfe yauzl, published on 11 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-31988 exists.

Affected packages and fixed versions:
- yauzl (npm): affected from 3.2.0; fixed in 3.2.1
- yauzl (npm): affected from 3.2.0; fixed in 3.2.1

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-2026-31988/ (Markdown: https://insights.sbomify.com/CVE-2026-31988/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-31988
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-31988
- OSV: https://osv.dev/vulnerability/CVE-2026-31988

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-31988/
Summaries are generated and may contain mistakes; the official description above is the record.