CyberSecBulletin
CVE-2026-77634NVD status: Deferred

cakephp: Improper Neutralization of CRLF Sequences

Published Updated By the CyberSecBulletin desk

CVE-2026-77634 is a high-severity improper neutralization of CRLF sequences vulnerability in cakephp, with a CVSS 4.0 base score of 8.2 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected cakephp versions: >= 4.5.0, < 4.5.12; >= 4.6.0, < 4.6.5; >= 5.0.0, < 5.1.9, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.31% 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 cakephp 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. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Cakephpcakephp>= 4.5.0, < 4.5.12; >= 4.6.0, < 4.6.5; >= 5.0.0, < 5.1.9; >= 5.2.0, < 5.2.14; >= 5.3.0, < 5.3.7Not 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
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Attack requirements
PresentThe target must be in a specific state or configuration for the attack to work.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Confidentiality (vulnerable system)
NoneNo loss of confidentiality on the vulnerable system.
Integrity (vulnerable system)
HighSerious loss of integrity on the vulnerable system.
Availability (vulnerable system)
NoneNo loss of availability on the vulnerable system.
Confidentiality (other systems)
NoneNo loss of confidentiality on systems beyond the vulnerable one.
Integrity (other systems)
NoneNo loss of integrity on systems beyond the vulnerable one.
Availability (other systems)
NoneNo loss of availability on systems beyond the vulnerable one.

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA (github.com).

Official description

CakePHP is a rapid development framework for PHP. Prior to versions 4.5.12, 4.6.5, 5.1.8, 5.2.14, and 5.3.7 on their respective release lines, custom mail headers added with Message::setHeaders() or Message::addHeaders() do not have CRLF bytes removed, allowing header injection when user-controlled data is used in message headers. This issue is fixed in versions 4.5.12, 4.6.5, 5.1.8, 5.2.14, and 5.3.7.

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

The underlying weakness: Improper Neutralization of CRLF Sequences

The product uses CRLF (carriage return line feeds) as a special element, e.g. to separate lines or records, but it does not neutralize or incorrectly neutralizes CRLF sequences from inputs.

How developers prevent this class of flaw

  • Appropriately filter or quote CRLF sequences in user-controlled input.

More Improper Neutralization of CRLF Sequences vulnerabilities (CWE-93)

Timeline

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

References

Other vulnerabilities in cakephp

All cakephp vulnerabilities

Recent Improper Neutralization of CRLF Sequences vulnerabilities

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