CVE-2017-7668

The HTTP strict parsing changes added in Apache httpd 2.2.32 and 2.4.24 introduced a bug in token list parsing, which allows ap_find_token() to search past the end of its input string. By maliciously crafting a sequence of request headers, an attacker may be able to cause a segmentation fault, or to force ap_find_token() to return an incorrect value.

Published: 2017-06-20 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2017-7668 is rated High Risk (66.5/100): CVSS High severity, with high exploitation likelihood (EPSS 64.83%, 98th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +2.05% over the last day, indicating growing attacker interest. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2017-7668

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-26 62.78% 64.83% +2.05%
2 2026-05-08 67.27% 62.78% -4.49%
3 2026-04-27 67.27%

Full EPSS history (67 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-7668

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
10.0 2.9 [email protected]

Weakness enumeration for CVE-2017-7668

OS Trackers for CVE-2017-7668

vendor priority summary link
alpine CVE-2017-7668: 1 source package rows (apache2); 10 state rows across 10 repos (3.10-main, 3.11-main, 3.12-main, 3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 10, open 0. https://security.alpinelinux.org/vuln/CVE-2017-7668
debian not yet assigned CVE-2017-7668 not yet assigned priority: Debian including 1 source packages (apache2), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2017-7668
gentoo normal CVE-2017-7668: 1 GLSA(s) (201710-32), 1 atom(s) (www-servers/apache); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2017-7668
redhat medium https://access.redhat.com/security/cve/CVE-2017-7668
ubuntu medium CVE-2017-7668 medium priority: Ubuntu including 1 source packages (apache2), 5 status rows across 5 suites (trusty, upstream, xenial, yakkety, zesty): released 4, pending 1. https://ubuntu.com/security/CVE-2017-7668

Affected software / configurations for CVE-2017-7668

Vendor Product Version Raw CPE
apache http_server 2.2.32 cpe:2.3:a:apache:http_server:2.2.32:*:*:*:*:*:*:*
apache http_server 2.4.24 cpe:2.3:a:apache:http_server:2.4.24:*:*:*:*:*:*:*
apache http_server 2.4.25 cpe:2.3:a:apache:http_server:2.4.25:*:*:*:*:*:*:*
netapp clustered_data_ontap cpe:2.3:a:netapp:clustered_data_ontap:-:*:*:*:*:*:*:*
netapp oncommand_unified_manager cpe:2.3:a:netapp:oncommand_unified_manager:-:*:*:*:*:7-mode:*:*
netapp storagegrid cpe:2.3:a:netapp:storagegrid:-:*:*:*:*:*:*:*
redhat enterprise_linux_desktop 7.0 cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*
redhat enterprise_linux_eus 7.2 cpe:2.3:o:redhat:enterprise_linux_eus:7.2:*:*:*:*:*:*:*
redhat enterprise_linux_eus 7.3 cpe:2.3:o:redhat:enterprise_linux_eus:7.3:*:*:*:*:*:*:*
redhat enterprise_linux_eus 7.4 cpe:2.3:o:redhat:enterprise_linux_eus:7.4:*:*:*:*:*:*:*
redhat enterprise_linux_eus 7.5 cpe:2.3:o:redhat:enterprise_linux_eus:7.5:*:*:*:*:*:*:*
redhat enterprise_linux_eus 7.6 cpe:2.3:o:redhat:enterprise_linux_eus:7.6:*:*:*:*:*:*:*
redhat enterprise_linux_eus 7.7 cpe:2.3:o:redhat:enterprise_linux_eus:7.7:*:*:*:*:*:*:*
redhat enterprise_linux_server 7.0 cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 7.2 cpe:2.3:o:redhat:enterprise_linux_server_aus:7.2:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 7.3 cpe:2.3:o:redhat:enterprise_linux_server_aus:7.3:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 7.4 cpe:2.3:o:redhat:enterprise_linux_server_aus:7.4:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 7.6 cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 7.7 cpe:2.3:o:redhat:enterprise_linux_server_aus:7.7:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 7.2 cpe:2.3:o:redhat:enterprise_linux_server_tus:7.2:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 7.3 cpe:2.3:o:redhat:enterprise_linux_server_tus:7.3:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 7.4 cpe:2.3:o:redhat:enterprise_linux_server_tus:7.4:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 7.6 cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 7.7 cpe:2.3:o:redhat:enterprise_linux_server_tus:7.7:*:*:*:*:*:*:*
redhat enterprise_linux_workstation 7.0 cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
oracle secure_global_desktop 5.3 cpe:2.3:a:oracle:secure_global_desktop:5.3:*:*:*:*:*:*:*
apple mac_os_x < 10.13.1 cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
apple mac_os_x >= 10.11.0, < 10.11.6 cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
apple mac_os_x >= 10.12.0, < 10.12.6 cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
apple mac_os_x 10.11.6 cpe:2.3:o:apple:mac_os_x:10.11.6:-:*:*:*:*:*:*
apple mac_os_x 10.11.6 cpe:2.3:o:apple:mac_os_x:10.11.6:security_update_2016-001:*:*:*:*:*:*
apple mac_os_x 10.11.6 cpe:2.3:o:apple:mac_os_x:10.11.6:security_update_2016-002:*:*:*:*:*:*
apple mac_os_x 10.11.6 cpe:2.3:o:apple:mac_os_x:10.11.6:security_update_2016-003:*:*:*:*:*:*
apple mac_os_x 10.11.6 cpe:2.3:o:apple:mac_os_x:10.11.6:security_update_2017-001:*:*:*:*:*:*
apple mac_os_x 10.11.6 cpe:2.3:o:apple:mac_os_x:10.11.6:security_update_2017-002:*:*:*:*:*:*
apple mac_os_x 10.11.6 cpe:2.3:o:apple:mac_os_x:10.11.6:security_update_2017-003:*:*:*:*:*:*
apple mac_os_x 10.12.6 cpe:2.3:o:apple:mac_os_x:10.12.6:-:*:*:*:*:*:*

References for CVE-2017-7668

URL Tags
http://www.debian.org/security/2017/dsa-3896 Third Party Advisory
http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html Patch Third Party Advisory
http://www.securityfocus.com/bid/99137 Third Party Advisory VDB Entry
http://www.securitytracker.com/id/1038711 Third Party Advisory VDB Entry
https://access.redhat.com/errata/RHSA-2017:2479 Third Party Advisory
https://access.redhat.com/errata/RHSA-2017:2483 Third Party Advisory
https://access.redhat.com/errata/RHSA-2017:3193 Third Party Advisory
https://access.redhat.com/errata/RHSA-2017:3194 Third Party Advisory
https://lists.apache.org/thread.html/55a068b6a5eec0b3198ae7d96a7cb412352d0ffa7716612c5af3745b%40%3Cdev.httpd.apache.org%3E
https://lists.apache.org/thread.html/56c2e7cc9deb1c12a843d0dc251ea7fd3e7e80293cde02fcd65286ba%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/84a3714f0878781f6ed84473d1a503d2cc382277e100450209231830%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/8d63cb8e9100f28a99429b4328e4e7cebce861d5772ac9863ba2ae6f%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/f7f95ac1cd9895db2714fa3ebaa0b94d0c6df360f742a40951384a53%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r15f9aa4427581a1aecb4063f1b4b983511ae1c9935e2a0a6876dad3c%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r476d175be0aaf4a17680ef98c5153b4d336eaef76fb2224cc94c463a%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r57608dc51b79102f3952ae06f54d5277b649c86d6533dcd6a7d201f7%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r6521a7f62276340eabdb3339b2aa9a38c5f59d978497a1f794af53be%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r75cbe9ea3e2114e4271bbeca7aff96117b50c1b6eb7c4772b0337c1f%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r9ea3538f229874c80a10af473856a81fbf5f694cd7f471cc679ba70b%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r9f93cf6dde308d42a9c807784e8102600d0397f5f834890708bf6920%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/rad01d817195e6cc871cb1d73b207ca326379a20a6e7f30febaf56d24%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/rc998b18880df98bafaade071346690c2bc1444adaa1a1ea464b93f0a%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/rcc44594d4d6579b90deccd4536b5d31f099ef563df39b094be286b9e%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/rd18c3c43602e66f9cdcf09f1de233804975b9572b0456cc582390b6f%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/rdca61ae990660bacb682295f2a09d34612b7bb5f457577fe17f4d064%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/re3d27b6250aa8548b8845d314bb8a350b3df326cacbbfdfe4d455234%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/rf6449464fd8b7437704c55f88361b66f12d5b5f90bcce66af4be4ba9%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/rfbaf647d52c1cb843e726a0933f156366a806cead84fbd430951591b%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/rfcf929bd33a6833e3f0c35eebdad70d5060665f9c4e17ea467c66770%40%3Ccvs.httpd.apache.org%3E
https://security.gentoo.org/glsa/201710-32 Third Party Advisory
https://security.netapp.com/advisory/ntap-20180601-0002/ Third Party Advisory
https://support.apple.com/HT208221 Third Party Advisory
https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03821en_us Third Party Advisory
https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03908en_us Third Party Advisory
https://www.tenable.com/security/tns-2019-09 Third Party Advisory
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