Vulnerability Name:

CVE-2020-12783 (CCN-181965)

Assigned:2020-05-05
Published:2020-05-05
Updated:2022-11-16
Summary:Exim through 4.93 has an out-of-bounds read in the SPA authenticator that could result in SPA/NTLM authentication bypass in auths/spa.c and auths/auth-spa.c.
CVSS v3 Severity:7.5 High (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N)
6.5 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/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): High
Integrity (I): None
Availibility (A): None
5.3 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)
4.6 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/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): Low
Availibility (A): None
CVSS v2 Severity:5.0 Medium (CVSS v2 Vector: AV:N/AC:L/Au:N/C:P/I:N/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): Partial
Integrity (I): None
Availibility (A): None
5.0 Medium (CCN CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:P/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Athentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): Partial
Availibility (A): None
Vulnerability Type:CWE-125
Vulnerability Consequences:Bypass Security
References:Source: MITRE
Type: CNA
CVE-2020-12783

Source: MLIST
Type: Exploit, Mailing List, Third Party Advisory
[oss-security] 20210504 21Nails: Multiple vulnerabilities in Exim

Source: CCN
Type: Bugzilla – Bug 2571
(CVE-2020-12783) Out-of-bound buffer read leads to Authentication Bypass in Exim SPA authentication method

Source: CONFIRM
Type: Third Party Advisory
https://bugs.exim.org/show_bug.cgi?id=2571

Source: XF
Type: UNKNOWN
exim-cve202012783-sec-bypass(181965)

Source: CONFIRM
Type: Patch, Third Party Advisory
https://git.exim.org/exim.git/commit/57aa14b216432be381b6295c312065b2fd034f86

Source: CONFIRM
Type: Patch, Third Party Advisory
https://git.exim.org/exim.git/commit/a04174dc2a84ae1008c23b6a7109e7fa3fb7b8b0

Source: CCN
Type: Exim GIT Repository
git.exim.org Git - exim.git/commitdiff

Source: MLIST
Type: Mailing List, Third Party Advisory
[debian-lts-announce] 20200518 [SECURITY] [DLA 2213-1] exim4 security update

Source: FEDORA
Type: Mailing List, Third Party Advisory
FEDORA-2020-93d7305d71

Source: FEDORA
Type: Mailing List, Third Party Advisory
FEDORA-2020-2e084c987d

Source: UBUNTU
Type: Third Party Advisory
USN-4366-1

Source: DEBIAN
Type: Third Party Advisory
DSA-4687

Vulnerable Configuration:Configuration 1:
  • cpe:/a:exim:exim:*:*:*:*:*:*:*:* (Version <= 4.93)

    • Configuration 2:
  • cpe:/o:fedoraproject:fedora:31:*:*:*:*:*:*:*
  • OR cpe:/o:fedoraproject:fedora:32:*:*:*:*:*:*:*

    • Configuration 3:
  • cpe:/o:debian:debian_linux:8.0:*:*:*:*:*:*:*
  • OR cpe:/o:debian:debian_linux:9.0:*:*:*:*:*:*:*
  • OR cpe:/o:debian:debian_linux:10.0:*:*:*:*:*:*:*

    • Configuration 4:
  • cpe:/o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
  • OR cpe:/o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*
  • OR cpe:/o:canonical:ubuntu_linux:19.10:*:*:*:*:*:*:*
  • OR cpe:/o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*
  • OR cpe:/o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*

    • Configuration CCN 1:
  • cpe:/a:exim:exim:4.93:*:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    Oval Definitions
    Definition IDClassTitleLast Modified
    oval:org.opensuse.security:def:112207
    P
    		exim-4.94.2-4.2 on GA media (Moderate)
    2022-01-17
    oval:org.opensuse.security:def:100366
    P
    		 (Moderate)
    2021-12-16
    oval:org.opensuse.security:def:105738
    P
    		exim-4.94.2-4.2 on GA media (Moderate)
    2021-10-01
    oval:org.opensuse.security:def:93653
    P
    		Security update for exim (Critical)
    2021-05-20
    oval:org.opensuse.security:def:109831
    P
    		Security update for exim (Critical)
    2021-05-20
    oval:org.opensuse.security:def:96484
    P
    		Security update for exim (Critical)
    2021-05-20
    oval:org.opensuse.security:def:11216
    P
    		Security update for exim (Critical)
    2021-05-20
    oval:org.opensuse.security:def:11217
    P
    		Security update for exim (Critical)
    2021-05-20
    oval:org.opensuse.security:def:103174
    P
    		Security update for exim (Critical)
    2021-05-20
    oval:org.opensuse.security:def:107032
    P
    		Security update for exim (Critical)
    2021-05-20
    oval:org.opensuse.security:def:111368
    P
    		Security update for exim (Critical)
    2021-05-07
    BACK
    exim exim *
    fedoraproject fedora 31
    fedoraproject fedora 32
    debian debian linux 8.0
    debian debian linux 9.0
    debian debian linux 10.0
    canonical ubuntu linux 18.04
    canonical ubuntu linux 14.04
    canonical ubuntu linux 19.10
    canonical ubuntu linux 20.04
    canonical ubuntu linux 16.04
    exim exim 4.93