cbcvebase.
CVE-2020-1927
published 2020-04-02

CVE-2020-1927: In Apache HTTP Server 2.4.0 to 2.4.41, redirects configured with mod_rewrite that were intended to be self-referential might be fooled by encoded newlines and…

PriorityP344medium6.1CVSS 3.1
AVNACLPRNUIRSCCLILAN
EPSS
56.69%
99.0th percentile
In Apache HTTP Server 2.4.0 to 2.4.41, redirects configured with mod_rewrite that were intended to be self-referential might be fooled by encoded newlines and redirect instead to an an unexpected URL within the request URL.

Affected

24 ranges
VendorProductVersion rangeFixed in
apacheapache_http_server
apachehttp_server2.4.0 – 2.4.41
canonicalubuntu_linux
canonicalubuntu_linux
canonicalubuntu_linux
debianapache2< apache2 2.4.43-1 (bookworm)apache2 2.4.43-1 (bookworm)
debiandebian_linux
debiandebian_linux
fedoraprojectfedora
fedoraprojectfedora
opensuseleap
oraclecommunications_element_manager
oraclecommunications_element_manager
oraclecommunications_element_manager
oraclecommunications_session_report_manager
oraclecommunications_session_report_manager
oraclecommunications_session_report_manager
oraclecommunications_session_route_manager
oraclecommunications_session_route_manager
oraclecommunications_session_route_manager
oracleenterprise_manager_ops_center
oracleinstantis_enterprisetrack17.1 – 17.3
oraclesd-wan_aware
oraclezfs_storage_appliance_kit

Detection & IOCsextracted from sources · hover to see the quote

  • Look for encoded newlines (e.g., %0a, %0d) in HTTP request URLs targeting mod_rewrite redirect rules, which may indicate an open redirect exploitation attempt against CVE-2020-1927.
  • Focus detection on Apache HTTP Server versions 2.4.0 through 2.4.41 running mod_rewrite with self-referential redirect rules as the vulnerable attack surface.
  • The attack vector is remote and delivered over HTTP; monitor for anomalous redirect responses (3xx) from Apache servers where the Location header points to an unexpected external URL.
  • ·Only mod_rewrite configurations using self-referential redirects are vulnerable; not all mod_rewrite rules are affected.
  • ·Red Hat Enterprise Linux 5 and 6 ship with httpd versions outside the vulnerable range (2.4.0–2.4.41) and are not affected.

CVSS provenance

nvdv3.16.1MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
nvdv2.05.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:N
osv9.8CRITICAL
vendor_ubuntu9.8CRITICAL
vendor_debian6.1LOW
vendor_oracle6.1MEDIUM
vendor_redhat6.1MEDIUM
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