# CVE-2026-34970: MantisBT Bugnote Revision Page Leaks Private Issue Metadata After Issue Access Is Revoked

> Attackers can view private issue metadata via bugnote revision pages even after losing access to the parent issue.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 May 2026
- **Updated:** 20 May 2026
- **Also known as:** GHSA-crmx-4p49-46m2

## What is CVE-2026-34970?

CVE-2026-34970 is a medium-severity vulnerability in mantisbt, published on 19 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Mantis Bug Tracker (MantisBT) is an open source issue tracker. Versions 2.28.1 and prior allow a bugnote author to access the note's Revisions page after losing access to the parent private issue. This issue has been fixed in version 2.28.2.

Weakness: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2026-34970?

2 open source packages ship an affected version, including mantisbt/mantisbt.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `mantisbt/mantisbt` | Packagist | All versions | 2.28.2 |
| `mantisbt/mantisbt` | Packagist | All versions | 2.28.2 |

## How do I fix CVE-2026-34970?

Upgrade mantisbt/mantisbt to 2.28.2 or later.

## Is CVE-2026-34970 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-34970 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-34970 and fix it if it is affected.

What it is: CVE-2026-34970 is a medium-severity vulnerability in mantisbt, published on 19 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-34970 exists.

Affected packages and fixed versions:
- mantisbt/mantisbt (Packagist): affected all versions; fixed in 2.28.2
- mantisbt/mantisbt (Packagist): affected all versions; fixed in 2.28.2

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-2026-34970/ (Markdown: https://insights.sbomify.com/CVE-2026-34970/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-34970
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-34970
- OSV: https://osv.dev/vulnerability/CVE-2026-34970

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-34970/
Summaries are generated and may contain mistakes; the official description above is the record.