CVE-2017-9788

Severity: critical (CVSS 9.1 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 56.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2017-07-13 · updated 2026-06-17
Weakness: CWE-20

Description

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 products

Apache HTTP Server: through 2.2.33; from 2.4.0 through 2.4.26
macOS: before 10.13.1 — fixed in 10.13.1
Debian Linux: 8.0, 9.0
NetApp OnCommand Unified Manager for 7-Mode (core package): all versions
NetApp Storage Automation Store: all versions
Oracle Corporation Secure Global Desktop: 5.3
RedHat Enterprise Linux Desktop: 6.0, 7.0
RedHat Enterprise Linux Server: 6.0, 7.0
RedHat Enterprise Linux Server Aus: 7.2, 7.3, 7.4, 7.6
RedHat Enterprise Linux Server Eus: 6.7, 7.2, 7.3, 7.4, 7.5, 7.6
RedHat Enterprise Linux Server Tus: 7.2, 7.3, 7.4, 7.6
RedHat Enterprise Linux Workstation: 6.0, 7.0
RedHat Jboss Core Services: 1.0
Red Hat JBoss EAP: 6.0.0, 6.4.0
Red Hat JBoss Enterprise Web Server: 2.0.0

How to fix

Upgrade to a fixed version: macOS 10.13.1. Check the vendor advisory for mitigations.

References

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