cbcvebase.
CVE-2017-9788
published 2017-07-13

CVE-2017-9788: In Apache httpd before 2.2.34 and 2.4.x before 2.4.27, the value placeholder in [Proxy-]Authorization headers of type 'Digest' was not initialized or reset…

PriorityP181critical9.1CVSS 3.0
AVNACLPRNUINSUCHINAH
ITWVulnCheck KEV
Exploited in the wild
EPSS
56.77%
99.0th percentile
In Apache httpd before 2.2.34 and 2.4.x before 2.4.27, the value placeholder in [Proxy-]Authorization headers of type 'Digest' was not initialized or reset before or between successive key=value assignments by mod_auth_digest. Providing an initial key with no '=' assignment could reflect the stale value of uninitialized pool memory used by the prior request, leading to leakage of potentially confidential information, and a segfault in other cases resulting in denial of service.

Affected

34 ranges· showing 25
VendorProductVersion rangeFixed in
apachehttp_server<= 2.2.33
apachehttp_server2.4.0 – 2.4.26
apache_software_foundationapache_http_server
apache_software_foundationapache_http_server
applemac_os_x< 10.13.110.13.1
applemacos_high_sierra_10.13.1_security_update_2017-001_sierra_and_security_update_20
debianapache2< apache2 2.4.27-1 (bookworm)apache2 2.4.27-1 (bookworm)
debiandebian_linux
debiandebian_linux
oraclesecure_global_desktop
redhatenterprise_linux_desktop
redhatenterprise_linux_desktop
redhatenterprise_linux_server
redhatenterprise_linux_server
redhatenterprise_linux_server_aus
redhatenterprise_linux_server_aus
redhatenterprise_linux_server_aus
redhatenterprise_linux_server_aus
redhatenterprise_linux_server_eus
redhatenterprise_linux_server_eus
redhatenterprise_linux_server_eus
redhatenterprise_linux_server_eus
redhatenterprise_linux_server_eus
redhatenterprise_linux_server_eus
redhatenterprise_linux_server_tus

Detection & IOCsextracted from sources · hover to see the quote

  • Attack targets [Proxy-]Authorization headers of type 'Digest' with a key provided without an '=' assignment, triggering uninitialized memory reflection or segfault in mod_auth_digest
  • Monitor for specially crafted Digest Authorization / Proxy-Authorization request headers sent to Apache httpd servers running mod_auth_digest; malformed headers lacking '=' in key=value pairs are the attack vector
  • Patch reference for source-level detection/diff: SVN revision 1800919 addresses the vulnerability in mod_auth_digest
  • ·If mod_auth_digest is not required, unload it to eliminate the attack surface entirely; verify removal with 'httpd -t -D DUMP_MODULES'
  • ·Affected versions are all Apache httpd through 2.2.33 and 2.4.26; fixed in 2.2.34 and 2.4.27

CVSS provenance

nvdv3.09.1CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
nvdv2.06.4MEDIUMAV:N/AC:L/Au:N/C:P/I:N/A:P
osv9.1CRITICAL
vulncheck9.1CRITICAL
vendor_debian9.1CRITICAL
vendor_redhat9.1CRITICAL
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