# CVE-2025-62796: PrivateBin persistent HTML injection in attachment filename enables redirect and defacement

> Attackers can inject persistent HTML via attachment filenames in PrivateBin, enabling redirects and defacement if attachments are enabled.

- **Severity:** Medium 5.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 28 Oct 2025
- **Updated:** 29 Oct 2025
- **Also known as:** GHSA-867c-p784-5q6g

## What is CVE-2025-62796?

CVE-2025-62796 is a medium-severity cross-site scripting vulnerability in PrivateBin, published on 28 Oct 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

PrivateBin is an online pastebin where the server has zero knowledge of pasted data. Versions 1.7.7 through 2.0.1 allow persistent HTML injection via the unsanitized attachment filename (attachment_name) when attachments are enabled. An attacker can modify attachment_name before encryption so that, after decryption, arbitrary HTML is inserted unescaped into the page near the file size hint, enabling redirect (e.g., meta refresh) and site defacement and related phishing attacks. Script execution is normally blocked by the recommended Content Security Policy, limiting confidentiality impact. The issue was introduced in 1.7.7 and fixed in 2.0.2. Update to 2.0.2 or later. Workarounds include enforcing the recommended CSP, deploying PrivateBin on a separate domain, or disabling attachments.

Weakness: CWE-80 (Improper Neutralization of Script-Related HTML Tags in a Web Page), CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2025-62796?

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


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `privatebin/privatebin` | Packagist | From 1.7.7 | 2.0.2 |
| `privatebin/privatebin` | Packagist | From 1.7.7 | 2.0.2 |

## How do I fix CVE-2025-62796?

Upgrade privatebin/privatebin to 2.0.2 or later.

## Is CVE-2025-62796 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-62796 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-62796 and fix it if it is affected.

What it is: CVE-2025-62796 is a medium-severity cross-site scripting vulnerability in PrivateBin, published on 28 Oct 2025. 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-2025-62796 exists.

Affected packages and fixed versions:
- privatebin/privatebin (Packagist): affected from 1.7.7; fixed in 2.0.2
- privatebin/privatebin (Packagist): affected from 1.7.7; fixed in 2.0.2

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-2025-62796/ (Markdown: https://insights.sbomify.com/CVE-2025-62796/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-62796
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-62796
- OSV: https://osv.dev/vulnerability/CVE-2025-62796

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-62796/
Summaries are generated and may contain mistakes; the official description above is the record.