vulntracker.iovulntracker.io
© 2026 vulntracker.io

CVE-2023-30536

Insecure header validation in slim/psr7

MEDIUM
6.5
CVSS Score
Published: April 17, 2023 at 09:17 PM UTC
Updated: June 17, 2026 at 05:54 AM UTC
2 products affected across 2 vendorsSlim Psr 7Slim Psr 7

Using Slim-Psr7 by slimphp?

Get instant alerts when new vulnerabilities affect Slim-Psr7 - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Start FreeSign In
Severity
MEDIUM6.5
Exploit prediction
EPSS 0.7%
SSVC
No known exploit

Description

slim/psr7 is a PSR-7 implementation for use with Slim 4. In versions prior to 1.6.1 an attacker could sneak in a newline (\n) into both the header names and values. While the specification states that \r\n\r\n is used to terminate the header list, many servers in the wild will also accept \n\n. An attacker that is able to control the header names that are passed to Slilm-Psr7 would be able to intentionally craft invalid messages, possibly causing application errors or invalid HTTP requests being sent out with an PSR-18 HTTP client. The latter might present a denial of service vector if a remote service’s web application firewall bans the application due to the receipt of malformed requests. The issue has been patched in version 1.6.1. There are no known workarounds to this issue. Users are advised to upgrade.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Slim Psr 7· Slimframework
95%
v < 1.6.1
Affected range stops below 1.6.1, so it looks safe — our inference, not a vendor statement
Slim Psr 7· Slimphp
60%
v < 1.6.1
Affected range stops below 1.6.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

References (3)

x_refsource_MISCPatch
Source: [email protected]
https://github.com/slimphp/Slim-Psr7/commit/ed1d553225dd190875d8814c47460daed4b550bb
x_refsource_CONFIRMVendor Advisory
Source: [email protected]
https://github.com/slimphp/Slim-Psr7/security/advisories/GHSA-q2qj-628g-vhfw
x_refsource_MISCTechnical Description
Source: [email protected]
https://www.rfc-editor.org/rfc/rfc7230#section-3.2.4

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.5MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
LOW
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-436

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Create accountSign in
Free plan, no card