# CVE-2026-90999: Sentry Seer vulnerability allows attacker-controlled input to be executed in a privileged environment

> Unauthenticated attackers can execute arbitrary code in Sentry Seer's privileged automation environment via fabricated telemetry events.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 16 Sep 2026
- **Updated:** 18 Sep 2026
- **Also known as:** GHSA-vh55-q5m4-8wr6

## What is CVE-2026-90999?

CVE-2026-90999 is a critical code injection vulnerability in Functional Software, Inc. Sentry Seer, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Sentry Seer is vulnerable to a multi-stage trust-boundary violation that allows unauthenticated attacker-controlled telemetry to become code that is executed by an agent in a privileged automation environment. An external attacker can submit fabricated Sentry events without having access to the victim’s Sentry account, source repository, or infrastructure.

Weakness: CWE-94 (Improper Control of Generation of Code), CWE-913 (Improper Control of Dynamically-Managed Code Resources), CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component), CWE-20 (Improper Input Validation), CWE-116 (Improper Encoding or Escaping of Output)

## Which versions are affected by CVE-2026-90999?


## How do I fix CVE-2026-90999?

No fix has been published for CVE-2026-90999 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-90999 being exploited?

There is no known exploitation of CVE-2026-90999 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90999 and fix it if it is affected.

What it is: CVE-2026-90999 is a critical code injection vulnerability in Functional Software, Inc. Sentry Seer, published on 16 Sep 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-2026-90999 in the wild and no public exploit code.

Affected product: Functional Software, Inc. Sentry Seer. 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-2026-90999/ (Markdown: https://insights.sbomify.com/CVE-2026-90999/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90999
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90999
- OSV: https://osv.dev/vulnerability/CVE-2026-90999

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90999/
Summaries are generated and may contain mistakes; the official description above is the record.