CVE-2026-40193: Maddy Mail Server: LDAP Filter Injection via Unsanitized Username
Noroxi assessment
Priority: Monitor (action score 32/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.41% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- According to CISA the attack is automatable: targets can be found by mass scanning.
- Fixed version: foxcpp maddy 0.9.3.
Low priority for now. Upgrade to foxcpp maddy 0.9.3 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
maddy is a composable, all-in-one mail server. Versions prior to 0.9.3 contain an LDAP injection vulnerability in the auth.ldap module where user-supplied usernames are interpolated into LDAP search filters and DN strings via strings.ReplaceAll() without any LDAP filter escaping, despite the go-ldap/ldap/v3 library's ldap.EscapeFilter() function being available in the same import. This affects three code paths: the Lookup() filter, the AuthPlain() DN template, and the AuthPlain() filter. An attacker with network access to the SMTP submission or IMAP interface can inject arbitrary LDAP filter expressions through the username field in AUTH PLAIN or LOGIN commands. This enables identity spoofing by manipulating filter results to authenticate as another user, LDAP directory enumeration via wildcard filters, and blind extraction of LDAP attribute values using authentication responses as a boolean oracle or via timing side-channels between the two distinct failure paths. This issue has been fixed in version 0.9.3.
- Published
- Apr 16, 2026
- Updated
- Oct 26, 2026
- EPSS
- 0.4% · 36th percentile
- CWE
- CWE-90
Report tools
Action score
32
Monitor
Low priority for now.
- CVSS
- 32 / 40 · 8.2 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.4%
CISA SSVC decision
- Exploitation
- proof of concept
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · GitHub_M
- 8.2
- NVD has not scored this yet; the score shown is the CNA’s.
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| maddy project | maddy | cpe:2.3:a:maddy_project:maddy |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- maddy project maddybefore 0.9.3
Versions reported by the vendor
Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.
foxcpp maddy
- < 0.9.3affected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Alpine:v3.23 | maddy | before 0.9.3-r0 | 0.9.3-r0 |
| Go | github.com/foxcpp/maddy | before 0.9.3 | 0.9.3 |
Same product
maddy project: all recordsOther highest-scoring records for the same primary product.
- CVE-2023-27582Full authentication bypass if SASL authorization username is specified39Monitor
- CVE-2022-24732Maddy Mail Server does not implement account expiry35Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| foxcpp maddy | 0.9.3 · description | Vendor (CNA) |
| alpine:maddy | 0.9.3-r0 · Alpine:v3.23 | Package registry (OSV) |
| Go:github.com/foxcpp/maddy | 0.9.3 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- low · data or configuration can be modified
- Availability
- none
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- Low
- Availability impact
- None
Weakness class (CWE)
CWE-90 · Improper Neutralization of Special Elements used in an LDAP Query ('LDAP Injection')CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log
- Fix✗ → ✓
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References
Show all references (1 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.