CVE-2020-28026
published 2021-05-06CVE-2020-28026: Exim 4 before 4.94.2 has Improper Neutralization of Line Delimiters, relevant in non-default configurations that enable Delivery Status Notification (DSN)…
PriorityP268critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
9.29%
94.7th percentile
Exim 4 before 4.94.2 has Improper Neutralization of Line Delimiters, relevant in non-default configurations that enable Delivery Status Notification (DSN). Certain uses of ORCPT= can place a newline into a spool header file, and indirectly allow unauthenticated remote attackers to execute arbitrary commands as root.
Affected
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | exim4 | < exim4 4.94.2-1 (bookworm) | exim4 4.94.2-1 (bookworm) |
| exim | exim | >= 4.00 < 4.94.2 | 4.94.2 |
Detection & IOCsextracted from sources · hover to see the quote
- →Look for SMTP RCPT TO commands containing ORCPT= parameter with embedded newline characters (\n or \r\n), which may indicate exploitation of spool header file injection ↗
- →Exploitation is only possible on Exim instances with Delivery Status Notification (DSN) enabled (non-default); filter SMTP traffic for DSN-related ORCPT= parameters containing line delimiter characters ↗
- ·Vulnerability only applies to Exim 4 versions before 4.94.2; instances running 4.94.2 or later are not affected ↗
- ·DSN (Delivery Status Notification) must be explicitly enabled in the Exim configuration for this vulnerability to be exploitable; it is not enabled by default ↗
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.09.3CRITICALAV:N/AC:M/Au:N/C:C/I:C/A:C
osv9.8CRITICAL
vendor_debian9.8CRITICAL
vendor_ubuntu9.8CRITICAL
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GHSA
GHSA-gf8c-vh34-8jv5: Exim 4 before 4
ghsa_unreviewed·2022-05-24
CVE-2020-28026 [CRITICAL] CWE-88 GHSA-gf8c-vh34-8jv5: Exim 4 before 4
Exim 4 before 4.94.2 has Improper Neutralization of Line Delimiters, relevant in non-default configurations that enable Delivery Status Notification (DSN). Certain uses of ORCPT= can place a newline into a spool header file, and indirectly allow unauthenticated remote attackers to execute arbitrary commands as root.
OSV
CVE-2020-28026: Exim 4 before 4
osv·2021-05-06·CVSS 9.8
CVE-2020-28026 [CRITICAL] CVE-2020-28026: Exim 4 before 4
Exim 4 before 4.94.2 has Improper Neutralization of Line Delimiters, relevant in non-default configurations that enable Delivery Status Notification (DSN). Certain uses of ORCPT= can place a newline into a spool header file, and indirectly allow unauthenticated remote attackers to execute arbitrary commands as root.
OSV
exim4 vulnerabilities
osv·2021-05-06·CVSS 9.8
CVE-2020-28026 [CRITICAL] exim4 vulnerabilities
exim4 vulnerabilities
USN-4934-1 fixed several vulnerabilities in Exim. This update provides
the corresponding update for Ubuntu 14.04 ESM and Ubuntu 16.04 ESM.
CVE-2020-28026 only affected Ubuntu 16.04 ESM.
Original advisory details:
It was discovered that Exim contained multiple security issues. An attacker
could use these issues to cause a denial of service, execute arbitrary
code remotely, obtain sensitive information, or escalate local privileges.
Ubuntu
Exim vulnerabilities
vendor_ubuntu·2021-05-06·CVSS 9.8
CVE-2020-28011 [CRITICAL] Exim vulnerabilities
Title: Exim vulnerabilities
Summary: Several security issues were fixed in Exim.
USN-4934-1 fixed several vulnerabilities in Exim. This update provides
the corresponding update for Ubuntu 14.04 ESM and Ubuntu 16.04 ESM.
CVE-2020-28026 only affected Ubuntu 16.04 ESM.
Original advisory details:
It was discovered that Exim contained multiple security issues. An attacker
could use these issues to cause a denial of service, execute arbitrary
code remotely, obtain sensitive information, or escalate local privileges.
Instructions: In general, a standard system update will make all the necessary changes.
Ubuntu
Exim vulnerabilities
vendor_ubuntu·2021-05-04
CVE-2020-28022 Exim vulnerabilities
Title: Exim vulnerabilities
Summary: Several security issues were fixed in Exim.
It was discovered that Exim contained multiple security issues. An attacker
could use these issues to cause a denial of service, execute arbitrary
code remotely, obtain sensitive information, or escalate local privileges.
Instructions: In general, a standard system update will make all the necessary changes.
Debian
CVE-2020-28026: exim4 - Exim 4 before 4.94.2 has Improper Neutralization of Line Delimiters, relevant in...
vendor_debian·2020·CVSS 9.8
CVE-2020-28026 [CRITICAL] CVE-2020-28026: exim4 - Exim 4 before 4.94.2 has Improper Neutralization of Line Delimiters, relevant in...
Exim 4 before 4.94.2 has Improper Neutralization of Line Delimiters, relevant in non-default configurations that enable Delivery Status Notification (DSN). Certain uses of ORCPT= can place a newline into a spool header file, and indirectly allow unauthenticated remote attackers to execute arbitrary commands as root.
Scope: local
bookworm: resolved (fixed in 4.94.2-1)
bullseye: resolved (fixed in 4.94.2-1)
forky: resolved (fixed in 4.94.2-1)
sid: resolved (fixed in 4.94.2-1)
trixie: resolved (fixed in 4.94.2-1)
No detection rules found.
No public exploits indexed.
2021-05-06
Published