Host Header Injection in e107 Password Reset Mechanism

e107 is a content management system (CMS). Prior to 2.3.4, a Host Header Injection vulnerability in the password reset page allows attackers to manipulate the Host header to generate password reset links pointing to attacker-controlled domains. This can lead to phishing attacks, account takeover, or other security risks. The severity is high, as the vulnerability affects a critical function related to user authentication. This vulnerability is fixed in 2.3.4.

Casky was already ahead

This CVE exploits attack patterns that Casky's 301matched skills already investigate — long before this vulnerability was disclosed. Claude's reasoning model maps these techniques to MITRE ATT&CK, so practitioners who ran these skills have already seen the threat behaviour in their findings.

Analysis

e107 CMS versions prior to 2.3.4 contain a Host Header Injection vulnerability in the password reset functionality that allows attackers to manipulate HTTP Host headers and generate fraudulent password reset links pointing to attacker-controlled domains. This vulnerability is particularly dangerous because it targets a critical authentication flow—password recovery—which users trust implicitly. Any organization running e107 CMS for content management, community sites, or intranet portals is at risk of account takeover through phishing attacks, where victims receive legitimate-looking password reset emails directing them to malicious sites to harvest credentials.

Casky's 301 matched skills leverage Claude AI with extended reasoning to detect the attack patterns underlying this vulnerability across MITRE ATT&CK techniques TA0001 (Initial Access) and TA0043 (Reconnaissance). Practitioners using Casky would observe skill detections flagging suspicious Host header manipulation attempts, anomalous password reset request patterns, and outbound link generation pointing to external domains during authentication workflows. The platform's security skills would highlight CWE-20 (Improper Input Validation) and CWE-807 (Reliance on Untrusted Inputs) patterns—specifically instances where user-supplied Host headers are reflected in password reset communications without proper validation. This enables practitioners to identify both active exploitation attempts and misconfigurations in their e107 deployments before attackers can weaponize the password reset mechanism for phishing campaigns.

Live Threat IntelligenceComing soon

Casky Risk Score

—

EPSS Probability

—

Shodan Exposure

—

GreyNoise Signal

—

Composite risk scoring from EPSS, CISA KEV, Shodan, and GreyNoise — 21 security APIs correlated into a single Casky Risk Score. Coming in Casky Pro. Join early access →

301 Casky skills cover this attack pattern

These skills use Claude AI's reasoning model to surface findings in the same attack categories as CVE-2026-43935.

analyzing-apt-group-with-mitre-navigator

threat intelligence · low

Run

analyzing-campaign-attribution-evidence

threat intelligence · low

Run

analyzing-certificate-transparency-for-phishing

threat intelligence · low

Run

MITRE ATT&CK Techniques

TA0001 TA0043

Investigate the attack patterns behind CVE-2026-43935

Casky has 301 skills that investigate the attack patterns behind CVE-2026-43935. Run one and get CVSS-scored findings in 3 minutes.

Run the skill that detects this →

X Instagram LinkedIn