CyberSecBulletin
CVE-2026-65954NVD status: Deferred

PHPCSUtils: Improper Neutralization of Directives in Dynamically Evaluated Code

CVE-2026-65954 is a high-severity improper neutralization of directives in dynamically evaluated code vulnerability in PHPCSUtils from PHPCSStandards, with a CVSS 3.1 base score of 8.6 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected PHPCSUtils versions: >= 1.0.0-alpha1, <= 1.2.2. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.15% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of PHPCSUtils you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
PHPCSStandardsPHPCSUtils>= 1.0.0-alpha1, <= 1.2.2Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H. Scored by CNA (github.com).

Official description

PHPCSUtils is a suite of utility functions for use with PHP_CodeSniffer. From 1.0.0-alpha1 until 1.2.3, PHPCSUtils\AbstractSniffs\AbstractArrayDeclarationSniff::getActualArrayKey() evaluates attacker-controlled array-key expressions with eval(), allowing callback-form keys in untrusted PHP code scanned by an extending sniff to execute arbitrary commands on the scanning host. Known reachable paths include Universal.Arrays.DuplicateArrayKey and Universal.Arrays.MixedArrayKeyTypes. This issue is fixed in version 1.2.3.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Neutralization of Directives in Dynamically Evaluated Code

The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes code syntax before using the input in a dynamic evaluation call (e.g. eval).

How developers prevent this class of flaw

  • If possible, refactor your code so that it does not need to use eval() at all.
  • For Python programs, it is frequently encouraged to use the ast.literal_eval() function instead of eval, since it is intentionally designed to avoid executing code. However, an adversary could still cause excessive memory or stack consumption via deeply nested structures, so the python documentation discourages use of ast.literal_eval() on untrusted data.

More Improper Neutralization of Directives in Dynamically Evaluated Code vulnerabilities (CWE-95)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Improper Neutralization of Directives in Dynamically Evaluated Code vulnerabilities

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