Vulnerability Name:

CVE-2021-44686 (CCN-214656)

Assigned:2021-11-23
Published:2021-11-23
Updated:2022-05-03
Summary:calibre before 5.32.0 contains a regular expression that is vulnerable to ReDoS (Regular Expression Denial of Service) in html_preprocess_rules in ebooks/conversion/preprocess.py.
CVSS v3 Severity:7.5 High (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
6.5 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): High
7.5 High (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
6.5 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): High
CVSS v2 Severity:5.0 Medium (CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Partial
7.8 High (CCN CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:N/A:C)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Athentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Complete
Vulnerability Type:CWE-400
Vulnerability Consequences:Denial of Service
References:Source: MITRE
Type: CNA
CVE-2021-44686

Source: MISC
Type: Exploit, Issue Tracking, Vendor Advisory
https://bugs.launchpad.net/calibre/+bug/1951979

Source: XF
Type: UNKNOWN
calibre-cve202144686-dos(214656)

Source: CCN
Type: GitHub Web site
ReDoS in calibre #18

Source: MISC
Type: Exploit, Issue Tracking, Patch, Third Party Advisory
https://github.com/dwisiswant0/advisory/issues/18

Source: CCN
Type: calibre GIT Repository
calibre

Source: MISC
Type: Patch, Third Party Advisory
https://github.com/kovidgoyal/calibre/compare/v5.31.1...v5.32.0

Source: FEDORA
Type: Mailing List, Third Party Advisory
FEDORA-2021-e42fadbcc3

Vulnerable Configuration:Configuration 1:
  • cpe:/a:calibre-ebook:calibre:*:*:*:*:*:*:*:* (Version < 5.32.0)

    • Configuration 2:
  • cpe:/o:fedoraproject:fedora:34:*:*:*:*:*:*:*

    • Configuration CCN 1:
  • cpe:/a:calibre-ebook:calibre:5.31.1:*:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    BACK
    calibre-ebook calibre *
    fedoraproject fedora 34
    calibre-ebook calibre 5.31.1