Vulnerabilities in pkg:golang/github.com/knadh/listmonk

PACKAGE
Advisory Identifier: GHSA-h5j9-cvrw-v5qh
Advisory Summary

CVE-2026-34828 is a HIGH (CVSS 7.1) listmonk's active sessions remain valid vulnerability (CWE-613: Insufficient Session Expiration) affecting Github.com/knadh/listmonk libraries in the Go ecosystem. The issue involves listmonk's active sessions remain valid after password reset and password change. Remediation is available by upgrading affected packages to version 1.1.1-0.20260329113754-1b5e8d38c778.

4 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:golang/github.com/knadh/listmonk

4 Known Advisory Record(s)

Vulnerability advisories affecting package pkg:golang/github.com/knadh/listmonk. Select an advisory below to view technical details or fixes.

Advisory ID CVE / NVD Severity Summary
GHSA-h5j9-cvrw-v5qh CVE-2026-34828 HIGH listmonk's active sessions remain valid after password reset and password change
GHSA-jmr4-p576-v565 CVE-2026-21483 MODERATE listmonk Vulnerable to Stored XSS Leading to Admin Account Takeover
GHSA-rf24-wg77-gq7w CVE-2025-58430 HIGH listmonk: CSRF to XSS Chain can Lead to Admin Account Takeover
GHSA-jc7g-x28f-3v3h CVE-2025-49136 CRITICAL listmonk's Sprig template Injection vulnerability leads to reading of Environment Variable for low privilege user

CVE-2026-34828 at a Glance

CVE Identifier CVE-2026-34828
GHSA Identifier GHSA-h5j9-cvrw-v5qh
Severity HIGH
CVSS v3.1 Base Score 7.1
CWE Classification CWE-613: Insufficient Session Expiration
Affected Product Github.com/knadh/listmonk
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 7.1

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity Low (I:L)
Availability None (A:N)

How to Fix CVE-2026-34828

To remediate this vulnerability, upgrade all affected Github.com/knadh/listmonk dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

github.com/knadh/listmonk fixed: 1.1.1-0.20260329113754-1b5e8d38c778
Upgrade github.com/knadh/listmonk to 1.1.1-0.20260329113754-1b5e8d38c778
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

inspect dependencies for github.com/knadh/listmonk

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-34828, inspect your project dependencies for Github.com/knadh/listmonk:

inspect dependencies for github.com/knadh/listmonk

Analyze the terminal output to locate any version of Github.com/knadh/listmonk in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.1.1-0.20260329113754-1b5e8d38c778), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-613: Insufficient Session Expiration, where according to wasc, "insufficient session expiration is when a web site permits an attacker to reuse old session credentials or session ids for authorization.". In Github.com/knadh/listmonk, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary A session management vulnerability allows previously issued authenticated sessions to remain valid after sensitive account security changes, specifically password reset and password change. As a result, an attacker who has already obtained a valid session cookie can retain access to the account even after the victim changes or resets their password. This weakens account recovery and session security guarantees. I reproduced the issue on listmonk v6.0.0. ### Details The application updates account credentials successfully, but existing active sessions are not revoked afterward. This behavior was confirmed in two flows: 1. **Password reset flow** - A user resets their password through the forgot/reset flow. - The old password becomes invalid. - The new password works. - However, a session cookie issued **before** the reset remains valid and continues to authenticate successfully. 2. **Authenticated password change flow** - The same user logs in from two separate sessions. - Using session A, the password is changed through the authenticated profile endpoint. - The old password becomes invalid. - The new password works. - However, session B, issued before the password change, remains valid and continues to authenticate successfully. From the source review, the reset flow consumes the reset token, updates the password, and creates a fresh session, but there does not appear to be any revocation of older sessions. The same applies to the profile password change flow. Relevant code areas observed during review: - `cmd/auth.go` — forgot/reset flow - `cmd/users.go` — authenticated profile update flow - `internal/core/users.go` — password update path Additionally: - It was verified that reset links are single-use. - It was verified that password reset on a TOTP-enabled account still enforces TOTP on fresh login. - However, already-issued sessions still remain valid after reset. ### PoC #### Case 1: Password reset does not revoke existing session 1. Create or use a normal user account. 2. Log in as that user and save the authenticated session cookie. 3. Trigger forgot-password for the account. 4. Use the emailed reset link and set a new password. 5. Verify: - the old password no longer works - the new password works 6. Replay the **old pre-reset session cookie** against an authenticated endpoint such as `/api/profile`. Example validation request: ```http GET /api/profile HTTP/1.1 Host: 127.0.0.1:9000 Cookie: session=<old_pre_reset_session> ``` Observed result: Server returns `HTTP/1.1 200 OK` Response contains the authenticated user profile #### Case 2: Password change does not revoke other active sessions 1. Log in twice as the same user and save two authenticated session cookies: - session A - session B 2. Using session A, change the password through the authenticated profile update endpoint. 3. Verify: - the old password no longer works - the new password works 4. Replay session B against an authenticated endpoint such as `/api/profile`. Example password change request: ```http PUT /api/profile HTTP/1.1 Host: 127.0.0.1:9000 Cookie: session=<session_A> Content-Type: application/json { "name":"victim1", "email":"victim1@test.local", "password":"VictimChanged123" } ``` Then validate session B: ```http GET /api/profile HTTP/1.1 Host: 127.0.0.1:9000 Cookie: session=<session_B> ``` Observed result: - Server returns `HTTP/1.1 200 OK` - Response contains the authenticated user profile ## Impact This issue allows persistence of unauthorized access after credential recovery actions. If an attacker has already stolen a valid session cookie through any means (for example malware, browser compromise, XSS, shared machine access, proxy leakage, or other session theft), the victim cannot fully recover the account by changing or resetting the password alone. The attacker’s existing session remains valid. This impacts account recovery expectations and session security for all authenticated users, including users with TOTP enabled. ## Attachment [listmonk-session-report.zip](https://github.com/user-attachments/files/25975979/listmonk-session-report.zip)

CVE-2026-34828 Affected Github.com/knadh/listmonk Versions

1 component(s)
Fixed Versions:
1.1.1-0.20260329113754-1b5e8d38c778
Product / Package Ecosystem Affected Versions Fixed Version
github.com/knadh/listmonk
Go
≥ 1.1.1-0.20241028090858-319053dd7a90
< 1.1.1-0.20260329113754-1b5e8d38c778
1.1.1-0.20260329113754-1b5e8d38c778

References

Frequently Asked Questions

What is CVE-2026-34828?
CVE-2026-34828 is a security vulnerability in Github.com/knadh/listmonk involving listmonk's active sessions remain valid after password reset and password change under CWE-613: Insufficient Session Expiration.
Which Github.com/knadh/listmonk versions are affected?
Affected versions include releases prior to 1.1.1-0.20260329113754-1b5e8d38c778 across affected packages: github.com/knadh/listmonk.
What version fixes CVE-2026-34828?
Upgrading to 1.1.1-0.20260329113754-1b5e8d38c778 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/knadh/listmonk affected?
Yes, github.com/knadh/listmonk is affected in releases prior to 1.1.1-0.20260329113754-1b5e8d38c778. Upgrade your dependency to 1.1.1-0.20260329113754-1b5e8d38c778 or later.
What is the CVSS score of CVE-2026-34828?
CVE-2026-34828 has a CVSS v3.1 base score of 7.1 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N.
What CWE is associated with CVE-2026-34828?
CVE-2026-34828 is classified under CWE-613: Insufficient Session Expiration (According to WASC, "Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization.").
How can I check Go dependencies for CVE-2026-34828?
Run the dependency tree command: 'inspect dependencies for github.com/knadh/listmonk'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-h5j9-cvrw-v5qh",
  "modified" : "2026-04-06T17:25:20Z",
  "published" : "2026-04-01T23:48:43Z",
  "aliases" : [ "CVE-2026-34828" ],
  "summary" : "listmonk's active sessions remain valid after password reset and password change",
  "details" : "### Summary\nA session management vulnerability allows previously issued authenticated sessions to remain valid after sensitive account security changes, specifically password reset and password change. As a result, an attacker who has already obtained a valid session cookie can retain access to the account even after the victim changes or resets their password.\n\nThis weakens account recovery and session security guarantees. I reproduced the issue on listmonk v6.0.0.\n\n### Details\nThe application updates account credentials successfully, but existing active sessions are not revoked afterward.\n\nThis behavior was confirmed in two flows:\n\n1. **Password reset flow**\n   - A user resets their password through the forgot/reset flow.\n   - The old password becomes invalid.\n   - The new password works.\n   - However, a session cookie issued **before** the reset remains valid and continues to authenticate successfully.\n\n2. **Authenticated password change flow**\n   - The same user logs in from two separate sessions.\n   - Using session A, the password is changed through the authenticated profile endpoint.\n   - The old password becomes invalid.\n   - The new password works.\n   - However, session B, issued before the password change, remains valid and continues to authenticate successfully.\n\nFrom the source review, the reset flow consumes the reset token, updates the password, and creates a fresh session, but there does not appear to be any revocation of older sessions. The same applies to the profile password change flow.\n\nRelevant code areas observed during review:\n- `cmd/auth.go` — forgot/reset flow\n- `cmd/users.go` — authenticated profile update flow\n- `internal/core/users.go` — password update path\n\nAdditionally:\n- It was verified that reset links are single-use.\n- It was verified that password reset on a TOTP-enabled account still enforces TOTP on fresh login.\n- However, already-issued sessions still remain valid after reset.\n\n### PoC\n#### Case 1: Password reset does not revoke existing session\n\n1. Create or use a normal user account.\n2. Log in as that user and save the authenticated session cookie.\n3. Trigger forgot-password for the account.\n4. Use the emailed reset link and set a new password.\n5. Verify:\n   - the old password no longer works\n   - the new password works\n6. Replay the **old pre-reset session cookie** against an authenticated endpoint such as `/api/profile`.\n\nExample validation request:\n```http\nGET /api/profile HTTP/1.1\nHost: 127.0.0.1:9000\nCookie: session=<old_pre_reset_session>\n```\n\nObserved result:\n\nServer returns `HTTP/1.1 200 OK`\nResponse contains the authenticated user profile\n\n#### Case 2: Password change does not revoke other active sessions\n\n1. Log in twice as the same user and save two authenticated session cookies:\n   - session A\n   - session B\n\n2. Using session A, change the password through the authenticated profile update endpoint.\n\n3. Verify:\n   - the old password no longer works\n   - the new password works\n\n4. Replay session B against an authenticated endpoint such as `/api/profile`.\n\nExample password change request:\n```http\nPUT /api/profile HTTP/1.1\nHost: 127.0.0.1:9000\nCookie: session=<session_A>\nContent-Type: application/json\n\n{\n  \"name\":\"victim1\",\n  \"email\":\"victim1@test.local\",\n  \"password\":\"VictimChanged123\"\n}\n```\n\nThen validate session B:\n```http\nGET /api/profile HTTP/1.1\nHost: 127.0.0.1:9000\nCookie: session=<session_B>\n```\n\nObserved result:\n- Server returns `HTTP/1.1 200 OK`\n- Response contains the authenticated user profile\n\n## Impact\n\nThis issue allows persistence of unauthorized access after credential recovery actions.\n\nIf an attacker has already stolen a valid session cookie through any means (for example malware, browser compromise, XSS, shared machine access, proxy leakage, or other session theft), the victim cannot fully recover the account by changing or resetting the password alone. The attacker’s existing session remains valid.\n\nThis impacts account recovery expectations and session security for all authenticated users, including users with TOTP enabled.\n\n## Attachment\n[listmonk-session-report.zip](https://github.com/user-attachments/files/25975979/listmonk-session-report.zip)",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/knadh/listmonk"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.1.1-0.20241028090858-319053dd7a90"
      }, {
        "fixed" : "1.1.1-0.20260329113754-1b5e8d38c778"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/knadh/listmonk/security/advisories/GHSA-h5j9-cvrw-v5qh"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-34828"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/knadh/listmonk/commit/db82035d619348949512dafdaf60c86037cafc9e"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/knadh/listmonk"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/knadh/listmonk/releases/tag/v6.1.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-613" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-04-01T23:48:43Z",
    "nvd_published_at" : "2026-04-02T18:16:33Z"
  }
}