PYSEC-2026-1228
Vulnerability from pysec - Published: 2026-07-07 16:02 - Updated: 2026-07-07 17:23ReDoS in strip_whitespaces() function in cps/string_helper.py in Calibre Web and Autocaliweb allows unauthenticated remote attackers to cause denial of service via specially crafted username parameter that triggers catastrophic backtracking during login. This issue affects Calibre Web: 0.6.24 (Nicolette); Autocaliweb: from 0.7.0 before 0.7.1.
| Name | purl | calibreweb | pkg:pypi/calibreweb |
|---|
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "calibreweb",
"purl": "pkg:pypi/calibreweb"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "0.6.24"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"0.6.12",
"0.6.13",
"0.6.14",
"0.6.15",
"0.6.16",
"0.6.17",
"0.6.18",
"0.6.19",
"0.6.20",
"0.6.21",
"0.6.22",
"0.6.23",
"0.6.24"
]
}
],
"aliases": [
"CVE-2025-6998",
"GHSA-2g7m-ph9x-7q7m"
],
"details": "ReDoS in strip_whitespaces() function in cps/string_helper.py in Calibre Web and Autocaliweb allows unauthenticated remote attackers to cause denial of service via specially crafted username parameter that triggers catastrophic backtracking during login. This issue affects Calibre Web: 0.6.24 (Nicolette); Autocaliweb: from 0.7.0 before 0.7.1.",
"id": "PYSEC-2026-1228",
"modified": "2026-07-07T17:23:52.607215Z",
"published": "2026-07-07T16:02:58.600303Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-6998"
},
{
"type": "WEB",
"url": "https://fluidattacks.com/advisories/megadeth"
},
{
"type": "WEB",
"url": "https://github.com/gelbphoenix/autocaliweb"
},
{
"type": "PACKAGE",
"url": "https://github.com/janeczku/calibre-web"
},
{
"type": "PACKAGE",
"url": "https://pypi.org/project/calibreweb"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-2g7m-ph9x-7q7m"
}
],
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Calibre Web and Autocaliweb have a ReDoS vulnerability"
}
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