LiveActive security incident?Get immediate response
CVE Record

CVE-2026-23760: SmarterTools SmarterMail < Build 9511 Authentication Bypass via Password Reset API

SmarterTools SmarterMail versions prior to build 9511 contain an authentication bypass vulnerability in the password reset API. The force-reset-password endpoint permits anonymous requests and fails to verify the existing password or a reset token when resetting system administrator accounts. An unauthenticated attacker can supply a target administrator username and a new password to reset the account, resulting in full administrative compromise of the SmarterMail instance. NOTE: SmarterMail system administrator privileges grant the ability to execute operating system commands via built-in management functionality, effectively providing administrative (SYSTEM or root) access on the underlying host.

CriticalCVSS 9.3Known exploitedUpdated
Discuss exposureBack to CVEs
Glexia's TakeSource changedcritical

Security readout for executives and security teams

Plain-English summary

Attackers can take over a vulnerable SmarterMail server without credentials by changing a system administrator’s password. Administrative access can then enable operating-system command execution, potentially giving attackers SYSTEM or root control of the underlying host.

Executive priority

Treat this as an emergency remediation and incident-response priority. Immediately upgrade exposed systems and investigate them for compromise because exploitation is documented and successful abuse can yield complete application and host control.

Technical view

SmarterMail builds before 9511 expose a password-reset API endpoint that accepts anonymous requests without validating the existing password or a reset token for system administrator accounts. Successful abuse produces full SmarterMail administrative access and may lead to privileged operating-system command execution through built-in management functionality.

Likely exposure

Any SmarterMail instance running a build before 9511 is affected. Risk is greatest where the vulnerable API is network-accessible, particularly from the internet. Exploitation requires no authentication, privileges, or user interaction.

Exploitation context

CISA lists CVE-2026-23760 in its Known Exploited Vulnerabilities catalog, supporting active exploitation in the wild. Public technical analysis also describes account takeover leading to operating-system command execution. The supplied evidence does not quantify exploitation prevalence or identify specific targeted sectors.

Researcher notes

The bundle’s structured affected-version entry is inconsistent, but its title, description, and referenced advisories identify builds before 9511 as vulnerable. No CPE is supplied. Validation should remain non-invasive and focus on version, exposure, administrative events, and host telemetry.

Mitigation direction

  • Upgrade every affected SmarterMail instance to build 9511 or later, following SmarterTools release guidance.
  • Temporarily restrict administrative and password-reset interfaces to trusted networks until upgrading.
  • Reset system administrator credentials after upgrading and invalidate active administrative sessions.
  • Investigate potentially exposed hosts for unauthorized administrator changes and operating-system activity.

Validation and detection

  • Inventory SmarterMail instances and confirm each installed build is 9511 or later.
  • Verify internet-facing instances do not expose vulnerable password-reset functionality before remediation.
  • Review SmarterMail audit records for unexpected administrator password resets, logins, or configuration changes.
  • Review host telemetry for suspicious command execution originating from SmarterMail services.
Prepared
Confidence
high
Sources
6

Public sources used

The source record changed after analysis: Material source record changed after analysis.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-288: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
description · low confidence lookup

Credential and access behavior lookup

The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2026-23760 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Critical
CVSS
9.3 (4.0)
Known Exploited
Yes
Published

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
4Timeline events
1ADP providers
7Source links

CISA KEV status

Status
Known exploited
Source
CISA-ADP
Date added
KEV reference

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: activeAutomatable: yesTechnical Impact: total

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
9.3CVSS 4.0CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N——VulnCheck

Vulnerability scoring details

Base CVSS 4.0 score

9.3Critical
CVSS 4.0 vector shape for CVE-2026-23760Attack VectorAttack ComplexityAttack RequirementsPrivileges RequiredUser InteractionVS ConfidentialityVS IntegrityVS AvailabilitySS ConfidentialitySS IntegritySS Availability

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Attack Requirements
NonePresent
Privileges Required
NoneLowHigh
User Interaction
NonePassiveActive
VS Confidentiality
HighLowNone
VS Integrity
HighLowNone
VS Availability
HighLowNone
SS Confidentiality
HighLowNone
SS Integrity
HighLowNone
SS Availability
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. Added to KEVCISA-ADP

    CISA Known Exploited Vulnerabilities metadata lists this CVE as known exploited.

  4. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvcother:kev

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
SmarterToolsSmarterMail0unaffected
Weakness

CWE details

CWE-288

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-288 · source CWE mapping

Authentication Bypass Using an Alternate Path or Channel

Authentication Bypass Using an Alternate Path or Channel represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs