# CVE-2015-1555: Auth bypass in n/a

> Remote attackers can create valid sessions without validation in Zend Framework, bypassing session security controls.

- **Severity:** Critical 9.1 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 7 Aug 2017
- **Updated:** 6 Aug 2024
- **Also known as:** GHSA-89c6-rprr-qfr3

## What is CVE-2015-1555?

CVE-2015-1555 is a critical authentication bypass vulnerability in n/a, published on 7 Aug 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Zend/Session/SessionManager in Zend Framework 2.2.x before 2.2.9, 2.3.x before 2.3.4 allows remote attackers to create valid sessions without using session validators.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2015-1555?

It affects 1 product.


Products: Zend Zend Framework.

## How do I fix CVE-2015-1555?

No fix has been published for CVE-2015-1555 yet. Limit exposure of the affected software until one is available.

## Is CVE-2015-1555 being exploited?

There is no known exploitation of CVE-2015-1555 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2020-29312](https://insights.sbomify.com/CVE-2020-29312/): Deserialization in n/a (critical 9.8)
- [CVE-2015-1786](https://insights.sbomify.com/CVE-2015-1786/): Zend Framework CSRF Vulnerability (high 8.8)
- [CVE-2015-7503](https://insights.sbomify.com/CVE-2015-7503/): Zend Framework Information Disclosure (high 7.5)
- [CVE-2014-2685](https://insights.sbomify.com/CVE-2014-2685/): Auth bypass in n/a (high 7.5)
- [CVE-2015-5161](https://insights.sbomify.com/CVE-2015-5161/): ZendXml and Zend Framework contain XXE and XEE Vulnerabilities (medium 6.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2015-1555 and fix it if it is affected.

What it is: CVE-2015-1555 is a critical authentication bypass vulnerability in n/a, published on 7 Aug 2017. 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-2015-1555 in the wild and no public exploit code.

Affected product: n/a. 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-2015-1555/ (Markdown: https://insights.sbomify.com/CVE-2015-1555/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2015-1555
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2015-1555
- OSV: https://osv.dev/vulnerability/CVE-2015-1555

---
From sbomify Insights: https://insights.sbomify.com/CVE-2015-1555/
Summaries are generated and may contain mistakes; the official description above is the record.