Patchfirst
CVE-2017-9798 Public exploit EPSS 95.0%

Apache httpd allows remote attackers to read secret data from process memory if the Limit directive can be set in a…

Apache Software Foundation · Apache HTTP Server

Summary

The flaw is in Apache HTTP Server (Apache Software Foundation), where a use-after-free in the handling of the Limit directive can cause secret data from process memory to be exposed. An unauthenticated remote attacker can exploit it by sending an OPTIONS HTTP request, but only when the Limit directive can be set in a user's .htaccess file or httpd.conf has certain misconfigurations, and the data returned depends on many configuration factors and is not always disclosed.

Official description · CVE.org

Apache httpd allows remote attackers to read secret data from process memory if the Limit directive can be set in a user's .htaccess file, or if httpd.conf has certain misconfigurations, aka Optionsbleed. This affects the Apache HTTP Server through 2.2.34 and 2.4.x through 2.4.27. The attacker sends an unauthenticated OPTIONS HTTP request when attempting to read secret data. This is a use-after-free issue and thus secret data is not always sent, and the specific data depends on many factors including configuration. Exploitation with .htaccess can be blocked with a patch to the ap_limit_section function in server/core.c.

Breakdown
71.7 / 100
Exploited
Yes, in VulnCheck KEV
Reports
0
Tactics
0/15

First seen exploited 4 years after disclosure. Public exploit code (Exploit-DB) was available the same day.

  1. DisclosedPublic exploit codeExploit-DBday 0
  2. First seen exploitedVulnCheck KEV evidence+4 yrs

techniques

No techniques linked

No ATT&CK techniques are linked to this CVE yet. MITRE CTID has not mapped it, and no report passage in the corpus ties it to a technique.

What security researchers reported

Not named in any threat report yet

Also mentioned in 5 community threat pulses (AlienVault OTX)

Weaker evidence

Pulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.

References

56 links, grouped by NVD tag

mailing-list 18

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