# OSV-2026-1189: Global-buffer-overflow in oidc_cfg_redirect_urls_allowed_get

> A global buffer overflow in the OIDC library allows attackers to cause denial of service or potentially execute code via crafted redirect URLs.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not stated
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 23 Aug 2026

## What is OSV-2026-1189?

OSV-2026-1189 is a memory corruption vulnerability in mod-auth-openidc, published on 23 Aug 2026. It can be exploited over the network, with no action from the victim.

### Official description

OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=550474749

```
Crash type: Global-buffer-overflow READ 8
Crash state:
oidc_cfg_redirect_urls_allowed_get
oidc_validate_redirect_url
fuzz_url.c
```

## Which versions are affected by OSV-2026-1189?

1 open source package ship an affected version, including mod-auth-openidc.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `mod-auth-openidc` | OSS-Fuzz | All versions | None |

## How do I fix OSV-2026-1189?

No fix has been published for OSV-2026-1189 yet. Limit exposure of the affected software until one is available.

## Is OSV-2026-1189 being exploited?

There is no known exploitation of OSV-2026-1189 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for OSV-2026-1189 and fix it if it is affected.

What it is: OSV-2026-1189 is a memory corruption vulnerability in mod-auth-openidc, published on 23 Aug 2026. It can be exploited over the network, with no action from the victim.
Exploitation: There is no known exploitation of OSV-2026-1189 in the wild and no public exploit code.

Affected packages and fixed versions:
- mod-auth-openidc (OSS-Fuzz): affected all versions; no fix listed

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/OSV-2026-1189/ (Markdown: https://insights.sbomify.com/OSV-2026-1189/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/OSV-2026-1189

---
From sbomify Insights: https://insights.sbomify.com/OSV-2026-1189/
Summaries are generated and may contain mistakes; the official description above is the record.