# CVE-2025-8836: JasPer JPEG2000 Encoder jpc_enc.c jpc_floorlog2 assertion

> A local attacker can trigger a reachable assertion in the JasPer JPEG2000 encoder, causing a denial of service.

- **Severity:** Medium 4.8 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 11 Aug 2025
- **Updated:** 12 Aug 2025
- **Also known as:** AZL-66165, AZL-66201, CLSA-2025-1760019942, CLSA-2025-1761074965, CLSA-2025-1765378381, GHSA-hvcg-67f3-52cf, UBUNTU-CVE-2025-8836

## What is CVE-2025-8836?

CVE-2025-8836 is a medium-severity denial of service vulnerability in Jasper Project Jasper, published on 11 Aug 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability was determined in JasPer up to 4.2.5. Affected by this issue is the function jpc_floorlog2 of the file src/libjasper/jpc/jpc_enc.c of the component JPEG2000 Encoder. The manipulation leads to reachable assertion. The attack needs to be approached locally. The exploit has been disclosed to the public and may be used. The patch is identified as 79185d32d7a444abae441935b20ae4676b3513d4. It is recommended to apply a patch to fix this issue.

Weakness: CWE-617 (Reachable Assertion)

## Which versions are affected by CVE-2025-8836?

It affects 1 product.


Products: Jasper Project Jasper.

## How do I fix CVE-2025-8836?

Apply the vendor's patch.

## Is CVE-2025-8836 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-8836 exists.

## Other vulnerabilities in Jasper Project Jasper

- [CVE-2008-3522](https://insights.sbomify.com/CVE-2008-3522/): Memory corruption in n/a (critical 10.0)
- [CVE-2008-3520](https://insights.sbomify.com/CVE-2008-3520/): Integer overflow in n/a (critical 9.3)
- [CVE-2015-8751](https://insights.sbomify.com/CVE-2015-8751/): Integer overflow in n/a (high 8.8)
- [CVE-2023-51257](https://insights.sbomify.com/CVE-2023-51257/): Memory corruption in n/a (high 7.8)
- [CVE-2016-8886](https://insights.sbomify.com/CVE-2016-8886/): Memory corruption in n/a (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-8836 and fix it if it is affected.

What it is: CVE-2025-8836 is a medium-severity denial of service vulnerability in Jasper Project Jasper, published on 11 Aug 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-8836 exists.

Affected product: Jasper Project Jasper. 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-2025-8836/ (Markdown: https://insights.sbomify.com/CVE-2025-8836/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-8836
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-8836
- OSV: https://osv.dev/vulnerability/CVE-2025-8836

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-8836/
Summaries are generated and may contain mistakes; the official description above is the record.