VDB-422279 · CVE-2026-91831 · EUVD-2026-104101

Subscribe to Comments Plugin up to 2.3.2 on WordPress Notification Sender Name Setting sender-name crlf injection

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
4.9	$0-$5k	5.40

Summaryinfo

A vulnerability marked as critical has been reported in Subscribe to Comments Plugin up to 2.3.2. Affected by this vulnerability is an unknown functionality of the component Notification Sender Name Setting. The manipulation of the argument sender-name leads to crlf injection. This vulnerability is traded as CVE-2026-91831. It is possible to initiate the attack remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Subscribe to Comments Plugin up to 2.3.2. It has been rated as critical. This issue affects an unknown code of the component Notification Sender Name Setting. The manipulation of the argument sender-name with an unknown input leads to a crlf injection vulnerability. Using CWE to declare the problem leads to CWE-93. 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. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

The Subscribe to Comments WordPress plugin before 2.3.3 does not sanitise newline characters from a notification sender-name setting before using it in e-mail headers, allowing users with Author-level access and above to inject arbitrary e-mail headers, such as a hidden Bcc, and to spoof the sender.

It is possible to read the advisory at wpscan.com. The identification of this vulnerability is CVE-2026-91831 since 09/15/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 2.3.3 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-104101). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

WordPress Plugin

Name

Subscribe to Comments Plugin

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.1
VulDB Meta Temp Score: 4.9

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 3.8
CNA Vector (WPScan): 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Crlf injection
CWE: CWE-93 / CWE-74 / CWE-707
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Subscribe to Comments Plugin 2.3.3

Timelineinfo

09/15/2026 CVE reserved
10/19/2026 +34 days Advisory disclosed
10/19/2026 +0 days VulDB entry created
10/19/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: wpscan.com
Status: Confirmed

CVE: CVE-2026-91831 (🔒)
GCVE (CVE): GCVE-0-2026-91831
GCVE (VulDB): GCVE-100-422279
EUVD: 🔒

Entryinfo

Created: 10/19/2026 09:00
Updated: 10/19/2026 10:54
Changes: 10/19/2026 09:00 (65), 10/19/2026 10:54 (1)
Complete: 🔍
Cache ID: 216::103