How severe is CVE-2015-2171?

No CVSS score has been assigned to CVE-2015-2171 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2015-2171?

CVE-2015-2171 affects the following packages: slim/slim (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2015-2171?

Update slim/slim to 2.6.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2015-2171 is resolved across your whole dependency graph.

How do I detect CVE-2015-2171 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for slim/slim, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2015-2171 if there is no patch (or I can't update yet)?

Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.

Is CVE-2015-2171 actively exploited in the wild?

No public exploit code has been indexed for CVE-2015-2171 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2015-2171?

CVE-2015-2171 has an EPSS (Exploit Prediction Scoring System) score of 2.5%, placing it in the 85th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2015-2171?

CVE-2015-2171 is classified as Code Injection (CWE-94). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2015-2171 published, and has it been updated?

CVE-2015-2171 was published on May 17, 2022 and was last updated on December 8, 2024. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘 Packagist

Not in CISA KEV

CVE-2015-2171 — slim

Fix: slimphp/Slim@9fa6514

CVE-2015-2171 is a Code Injection vulnerability in slim/slim. A fix is available for slim/slim — see the affected versions and patch details below.

Slim vulnerable to PHP object injection

Published

May 17, 2022

Updated

Dec 8, 2024

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 4, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

2.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs85th percentile — riskier than 85% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

1 pkg affected

🐘slim/slim

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

Middleware/SessionCookie.php in Slim before 2.6.0 allows remote attackers to conduct PHP object injection attacks and execute arbitrary PHP code via crafted session data.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`slim/slim`	all versions	2.6.0`composer require slim/slim:^2.6.0`

Affected Products

1 product · 1 configurations

Application

slimslimframework

≤ 2.5.0

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for slim/slim, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update slim/slim to 2.6.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2015-2171 is resolved across your whole dependency graph.
Workarounds
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.

Frequently Asked Questions

Middleware/SessionCookie.php in Slim before 2.6.0 allows remote attackers to conduct PHP object injection attacks and execute arbitrary PHP code via crafted session data.