# CVE-2026-53997: Netherman Portal del Hermano Account Takeover via Password Reset Oracle

> Unauthenticated attackers can take over any member account by exploiting password reset oracles and lack of rate limiting to bypass identity verification.

- **Severity:** Critical 9.1 (`CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Oct 2026
- **Updated:** 15 Oct 2026
- **Also known as:** GHSA-p44j-p338-ffrc

## What is CVE-2026-53997?

CVE-2026-53997 is a critical authentication bypass vulnerability in NetHerman Portal del Hermano (portaldelhermano.es), published on 12 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Netherman Portal del Hermano (portaldelhermano.es) before 2026-10-06 contains a broken authentication vulnerability in its password-recovery flow at the POST /password/create-access and POST /password/email endpoints, allowing unauthenticated attackers to take over any member account across all tenants by exploiting the lack of rate limiting and distinct error messages that act as oracles for each of the four identity-verification factors (DNI, date of birth, phone number, last four IBAN digits). Attackers can confirm the DNI via the oracle, brute-force the date of birth and IBAN digits, obtain the phone number through open-source intelligence, then submit an attacker-controlled email field so the password reset link is delivered to them, enabling full account takeover including profile data, full IBAN, and fiscal documents.

Weakness: CWE-640 (Weak Password Recovery Mechanism for Forgotten Password), CWE-307 (Improper Restriction of Excessive Authentication Attempts)

## Which versions are affected by CVE-2026-53997?


## How do I fix CVE-2026-53997?

No fix has been published for CVE-2026-53997 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-53997 being exploited?

There is no known exploitation of CVE-2026-53997 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-53997 and fix it if it is affected.

What it is: CVE-2026-53997 is a critical authentication bypass vulnerability in NetHerman Portal del Hermano (portaldelhermano.es), published on 12 Oct 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-2026-53997 in the wild and no public exploit code.

Affected product: NetHerman Portal del Hermano (portaldelhermano.es). 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-2026-53997/ (Markdown: https://insights.sbomify.com/CVE-2026-53997/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53997
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53997
- OSV: https://osv.dev/vulnerability/CVE-2026-53997

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53997/
Summaries are generated and may contain mistakes; the official description above is the record.