GHSA-527G-3W9M-29HV
Vulnerability from github – Published: 2026-04-14 01:08 – Updated: 2026-06-06 00:58Impact
In mitmproxy 12.2.1 and below, the builtin LDAP proxy authentication does not correctly sanitize the username when querying the LDAP server. This allows a malicious client to bypass authentication.
Only mitmproxy instances using the proxyauth option with LDAP are affected. This option is not enabled by default.
Patches
The vulnerability has been fixed in mitmproxy 12.2.2 and above.
Acknowledgements
We thank Yue (Knox) Liu (@yueyueL) for responsibly disclosing this vulnerability to the mitmproxy team.
Timeline
- 2025-12-08: Received initial report.
- 2025-12-09: Verified report and confirmed receipt.
- 2026-01-02: Informed researcher that patch will be part of the next regular patch release.
- 2026-04-12: Published patch release and advisory.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 12.2.1"
},
"package": {
"ecosystem": "PyPI",
"name": "mitmproxy"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "12.2.2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-40606"
],
"database_specific": {
"cwe_ids": [
"CWE-90"
],
"github_reviewed": true,
"github_reviewed_at": "2026-04-14T01:08:52Z",
"nvd_published_at": "2026-04-21T18:16:52Z",
"severity": "MODERATE"
},
"details": "### Impact\nIn mitmproxy 12.2.1 and below, the builtin LDAP proxy authentication does not correctly sanitize the username when querying the LDAP server. This allows a malicious client to bypass authentication.\n\nOnly mitmproxy instances using the `proxyauth` option with LDAP are affected. This option is not enabled by default.\n\n### Patches\n\nThe vulnerability has been fixed in mitmproxy 12.2.2 and above.\n\n### Acknowledgements\n\nWe thank Yue (Knox) Liu (@yueyueL) for responsibly disclosing this vulnerability to the mitmproxy team.\n\n### Timeline\n\n- **2025-12-08**: Received initial report. \n- **2025-12-09**: Verified report and confirmed receipt.\n- **2026-01-02**: Informed researcher that patch will be part of the next regular patch release.\n- **2026-04-12**: Published patch release and advisory.",
"id": "GHSA-527g-3w9m-29hv",
"modified": "2026-06-06T00:58:36Z",
"published": "2026-04-14T01:08:52Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/mitmproxy/mitmproxy/security/advisories/GHSA-527g-3w9m-29hv"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40606"
},
{
"type": "PACKAGE",
"url": "https://github.com/mitmproxy/mitmproxy"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/mitmproxy/PYSEC-2026-92.yaml"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "mitmproxy has an LDAP Injection"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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