# CVE-2026-47878: Unsafe Java deserialization in DefaultExecutionContextSerializer without class allowlist

> Attackers can execute arbitrary code via unsafe Java deserialization in Spring Batch's default JDBC job repository serializer.

- **Severity:** Medium 5.6 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 27 Aug 2026
- **Updated:** 27 Aug 2026
- **Also known as:** CLSA-2026-1791375028, GHSA-2pwq-qhmm-3vg8

## What is CVE-2026-47878?

CVE-2026-47878 is a medium-severity unsafe deserialization vulnerability in Spring Batch, published on 27 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

DefaultExecutionContextSerializer, used by default in Spring Batch's JDBC job repository, passes Base64-decoded bytes directly to ObjectInputStream.readObject() without an ObjectInputFilter that restricts types to a trusted class allowlist.
Spring Batch 6.0.0 - 6.0.4
Spring Batch 5.2.6 and earlier

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2026-47878?

It affects 1 product.


Products: Broadcom Spring Batch.

## How do I fix CVE-2026-47878?

Upgrade to a fixed version.

## Is CVE-2026-47878 being exploited?

There is no known exploitation of CVE-2026-47878 in the wild and no public exploit code.

## Other vulnerabilities in Spring Batch

- [CVE-2019-3774](https://insights.sbomify.com/CVE-2019-3774/): Spring Batch XML External Entity Injection (XXE) (critical 9.8)
- [CVE-2020-5411](https://insights.sbomify.com/CVE-2020-5411/): Jackson Configuration Allows Code Execution with Unknown "Serialization Gadgets" (high 8.1)
- [CVE-2026-47881](https://insights.sbomify.com/CVE-2026-47881/): Denial of Service in Spring Batch FlatFileItemReader via Malformed Input File (medium 5.9)
- [CVE-2026-47875](https://insights.sbomify.com/CVE-2026-47875/): JobParameterDeserializer bypasses the trusted-type allowlist (medium 5.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-47878 and fix it if it is affected.

What it is: CVE-2026-47878 is a medium-severity unsafe deserialization vulnerability in Spring Batch, published on 27 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-47878 in the wild and no public exploit code.

Affected product: Spring Batch. 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-2026-47878/ (Markdown: https://insights.sbomify.com/CVE-2026-47878/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-47878
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-47878
- OSV: https://osv.dev/vulnerability/CVE-2026-47878

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-47878/
Summaries are generated and may contain mistakes; the official description above is the record.