Vulnerability Name:

CVE-2020-23856 (CCN-202162)

Assigned:2020-07-09
Published:2020-07-09
Updated:2022-01-01
Summary:Use-after-Free vulnerability in cflow 1.6 in the void call(char *name, int line) function at src/parser.c, which could cause a denial of service via the pointer variable caller->callee.
CVSS v3 Severity:5.5 Medium (CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)
4.9 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:U/RC:R)
Exploitability Metrics:Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): High
4.0 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)
3.5 Low (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:U/RL:U/RC:R)
Exploitability Metrics:Attack Vector (AV): Local
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): Low
CVSS v2 Severity:2.1 Low (CVSS v2 Vector: AV:L/AC:L/Au:N/C:N/I:N/A:P)
Exploitability Metrics:Access Vector (AV): Local
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Partial
2.1 Low (CCN CVSS v2 Vector: AV:L/AC:L/Au:N/C:N/I:N/A:P)
Exploitability Metrics:Access Vector (AV): Local
Access Complexity (AC): Low
Athentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Partial
Vulnerability Type:CWE-416
Vulnerability Consequences:Denial of Service
References:Source: MITRE
Type: CNA
CVE-2020-23856

Source: XF
Type: UNKNOWN
cflow-cve202023856-dos(202162)

Source: MISC
Type: Exploit, Third Party Advisory
https://github.com/yangjiageng/PoC/blob/master/PoC_cflow_uaf_parser_line1284

Source: FEDORA
Type: Mailing List, Third Party Advisory
FEDORA-2021-6ef76430d0

Source: FEDORA
Type: Mailing List, Third Party Advisory
FEDORA-2021-e8cab459ab

Source: CCN
Type: GNU Mailing List, Thu, 9 Jul 2020 10:33:22 +0800
flow 1.6 void call(char name, int line) function Use-after-Free vuln

Source: MISC
Type: Exploit, Mailing List, Vendor Advisory
https://lists.gnu.org/archive/html/bug-cflow/2020-07/msg00000.html

Vulnerable Configuration:Configuration 1:
  • cpe:/a:gnu:cflow:1.6:*:*:*:*:*:*:*

  • Configuration 2:
  • cpe:/o:fedoraproject:fedora:33:*:*:*:*:*:*:*
  • OR cpe:/o:fedoraproject:fedora:34:*:*:*:*:*:*:*

  • Configuration CCN 1:
  • cpe:/a:gnu:cflow:1.6:*:*:*:*:*:*:*

  • * Denotes that component is vulnerable
    BACK
    gnu cflow 1.6
    fedoraproject fedora 33
    fedoraproject fedora 34
    gnu cflow 1.6