CVE-2017-9788
CriticalExploitedIn 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.
Published Jul 13, 2017 · Updated Sep 23, 2026 · Also known as DEBIAN-CVE-2017-9788, DLA-1028-1, DSA-3913-1, SUSE-SU-2017:1961-1, SUSE-SU-2017:1997-1, UBUNTU-CVE-2017-9788, USN-3370-1
Key Facts
Patch immediately- CVE-2017-9788 is a critical-severity vulnerability (CVSS 9.1 v3.1) affecting HTTP Server (Apache), Oncommand Unified Manager (Netapp), Storage Automation Store (Netapp) and 22 more products.
- It is exploited in the wild, listed in Industry KEV feed since Feb 22, 2022. No public exploit code is known.
- EPSS estimates a 57% probability of exploitation in the next 30 days.
- Fixed versions are available, including apache 2.4.27-1, HTTP Server 2.2.33, apache2 2.2.22-13+deb7u10.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
9.1
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
EPSS (30-day exploit likelihood)
57%
Higher than 99.0% of all scored CVEs
Exploited in the wild
Yes
1 catalog listing
Public exploit code
None known
Get the full CVE-2017-9788 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Feb 22, 2022 | n/a | Not reported |
Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected Products
199 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| HTTP ServerApache | >= 2.2.0 to 2.2.33 | 2.2.33 |
| Oncommand Unified ManagerNetapp | See advisory | n/a |
| Storage Automation StoreNetapp | See advisory | n/a |
| Secure Global DesktopOracle | 5.3 | n/a |
| Jboss Core ServicesRedhat | 1.0 | n/a |
Patched Releases
apache
2.4.27-1
HTTP Server
2.2.33
apache2
2.2.22-13+deb7u10, 2.2.34-70.5.1, 2.4.10-10+deb8u10, 2.4.10-14.28.1, 2.4.16-20.10.1, 2.4.18-2ubuntu3.4, 2.4.23-13.1, 2.4.23-29.3.2, 2.4.25-3+deb9u2, 2.4.27-1, 2.4.7-1ubuntu4.17
apache2-devel
2.2.34-70.5.1, 2.4.23-13.1, 2.4.23-29.3.2
apache2-doc
2.2.34-70.5.1, 2.4.10-14.28.1, 2.4.16-20.10.1, 2.4.23-13.1, 2.4.23-29.3.2
apache2-event
2.4.23-13.1
apache2-example-pages
2.2.34-70.5.1, 2.4.10-14.28.1, 2.4.16-20.10.1, 2.4.23-13.1, 2.4.23-29.3.2
apache2-prefork
2.2.34-70.5.1, 2.4.10-14.28.1, 2.4.16-20.10.1, 2.4.23-13.1, 2.4.23-29.3.2
apache2-utils
2.2.34-70.5.1, 2.4.10-14.28.1, 2.4.16-20.10.1, 2.4.23-13.1, 2.4.23-29.3.2
apache2-worker
2.2.34-70.5.1, 2.4.10-14.28.1, 2.4.16-20.10.1, 2.4.23-13.1, 2.4.23-29.3.2
Mac OS X
10.13.1
httpd
0:2.2.15-47.el6_7.5, 0:2.4.6-40.el7_2.6, 2.2.15-60.0.1.el6_9.5, 2.2.34-1.12.amzn1, 2.4.27-1.ph1, 2.4.28-1.ph2, 2.4.6-67.0.1.el7_4.2
httpd-devel
2.2.15-60.0.1.el6_9.5, 2.2.34-1.12.amzn1, 2.4.6-67.0.1.el7_4.2
httpd-manual
2.2.15-60.0.1.el6_9.5, 2.2.34-1.12.amzn1, 2.4.6-67.0.1.el7_4.2
httpd-tools
2.2.15-60.0.1.el6_9.5, 2.2.34-1.12.amzn1, 2.4.6-67.0.1.el7_4.2
httpd22
0:2.2.26-58.ep6.el7
httpd24-httpd
0:2.4.25-9.el6.1, 0:2.4.25-9.el7.1, 2.4.25-9.0.1.el6.1
httpd24-httpd-devel
2.4.25-9.0.1.el6.1
httpd24-httpd-manual
2.4.25-9.0.1.el6.1
httpd24-httpd-tools
2.4.25-9.0.1.el6.1
httpd24-mod_ldap
2.4.25-9.0.1.el6.1
httpd24-mod_proxy_html
1:2.4.25-9.0.1.el6.1
httpd24-mod_session
2.4.25-9.0.1.el6.1
httpd24-mod_ssl
1:2.4.25-9.0.1.el6.1
jbcs-httpd24-httpd
0:2.4.23-122.jbcs.el6, 0:2.4.23-122.jbcs.el7
Timeline
Publicly disclosed
Jul 13, 2017
Added to Industry KEV feed
Feb 22, 2022
Last updated
Sep 23, 2026
Weakness Type
- CWE-20 Improper Input Validation
- CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
- CWE-456 Missing Initialization of a Variable
References
- advisoryRHSA-2017:2478
- advisoryRHSA-2017:2479
- advisoryRHSA-2017:2483
- advisoryRHSA-2017:2708
- advisoryRHSA-2017:2709
FAQ
Common Questions.
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.
Affected: HTTP Server (Apache) versions >= 2.2.0 to 2.2.33; Oncommand Unified Manager (Netapp); Storage Automation Store (Netapp), among others. The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since Feb 22, 2022.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including apache 2.4.27-1, HTTP Server 2.2.33, apache2 2.2.22-13+deb7u10.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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