# CVE-2026-48102: GHSL-2026-118: 7-Zip UDF Field OOB Read

> A heap out-of-bounds read in 7-Zip's UDF handler allows attackers to disclose limited memory data or cause crashes via crafted ISO/UDF images.

- **Severity:** Low 3.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 5 Jun 2026
- **Updated:** 9 Jun 2026
- **Also known as:** ALPINE-CVE-2026-48102, DEBIAN-CVE-2026-48102, ECHO-ebb4-90fc-823e, MINI-2vgp-32mj-p6x8, UBUNTU-CVE-2026-48102

## What is CVE-2026-48102?

CVE-2026-48102 is a low-severity vulnerability in mcmilk 7-Zip, published on 5 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

7-Zip is a file archiver with a high compression ratio. Versions 9.11 through 26.00 contain a heap out-of-bounds read of up to 3 bytes in the UDF disc image handler's File Identifier Descriptor parser. In CFileId::Parse (CPP/7zip/Archive/Udf/UdfIn.cpp), after validating size < 38 + idLen + impLen and advancing processed to 38 + impLen + idLen, the alignment-padding loop reads p[processed] while incrementing up to 3 times to reach a 4-byte boundary, and the processed <= size bounds check only runs after the loop. When (38 + impLen + idLen) % 4 != 0 and 38 + impLen + idLen == size, the loop reads 1 to 3 bytes past the end of the exact-size heap buffer allocated via buf.Alloc((size_t)item.Size). The UDF handler is registered for .iso and .udf files and auto-detected by signature, and the OOB read triggers during Open() when listing or extracting a crafted UDF image. Impact is limited to information disclosure (a 1-bit oracle per OOB byte via open/fail behavior) and denial of service (crash under hardened allocators); there is no write primitive. Version 26.01 fixes the issue.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-48102?

It affects 1 product.


Products: 7-Zip 7-Zip.

## How do I fix CVE-2026-48102?

Upgrade to a fixed version.

## Is CVE-2026-48102 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-48102 exists.

## Other vulnerabilities in mcmilk 7-Zip

- [CVE-2025-0411](https://insights.sbomify.com/CVE-2025-0411/): 7-Zip Mark of the Web Bypass (high 7.0, exploited in the wild)
- [CVE-2008-6536](https://insights.sbomify.com/CVE-2008-6536/): Other in n/a (critical 10.0)
- [CVE-2026-48095](https://insights.sbomify.com/CVE-2026-48095/): GHSL-2026-140_7-Zip: 7-Zip has a heap buffer overflow via NTFS compressed stream buffer under-allocation (high 8.8)
- [CVE-2018-10172](https://insights.sbomify.com/CVE-2018-10172/): Privilege escalation in n/a (high 8.8)
- [CVE-2016-2335](https://insights.sbomify.com/CVE-2016-2335/): Memory corruption in n/a (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-48102 and fix it if it is affected.

What it is: CVE-2026-48102 is a low-severity vulnerability in mcmilk 7-Zip, published on 5 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-48102 exists.

Affected product: mcmilk 7-Zip. 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-2026-48102/ (Markdown: https://insights.sbomify.com/CVE-2026-48102/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-48102
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-48102
- OSV: https://osv.dev/vulnerability/CVE-2026-48102

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-48102/
Summaries are generated and may contain mistakes; the official description above is the record.