CVE-2020-11985 — IP address spoofing when proxying using mod_remoteip and mod_rewrite For configu

IP address spoofing when proxying using mod_remoteip and mod_rewrite For configurations using proxying with mod_remoteip and certain mod_rewrite rules, an attacker could spoof their IP address for logging and PHP scripts. Note this issue was fixed in Apache HTTP Server 2.4.24 but

01What is this vulnerability?

IP address spoofing when proxying using mod_remoteip and mod_rewrite For configurations using proxying with mod_remoteip and certain mod_rewrite rules, an attacker could spoof their IP address for logging and PHP scripts. Note this issue was fixed in Apache HTTP Server 2.4.24 but was retrospectively allocated a low severity CVE in 2020.

02Affected products

Vendor	Product	Versions
n	a / Apache HTTP Server	2.4.1 to 2.4.23

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2020-08-07T15:36:31.000Z
• Last modified: 2024-08-04T11:48:58.232Z

09References

• httpd.apache.org — https://httpd.apache.org/security/vulnerabilities_24.html
• security.gentoo.org — https://security.gentoo.org/glsa/202008-04
• lists.fedoraproject.org — https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro…
• lists.fedoraproject.org — https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro…
• www.oracle.com — https://www.oracle.com/security-alerts/cpujan2021.html
• security.netapp.com — https://security.netapp.com/advisory/ntap-20200827-0002/
• lists.apache.org — https://lists.apache.org/thread.html/rf6449464fd8b7437704c55f88361b66f12d5b5f90b…
• lists.apache.org — https://lists.apache.org/thread.html/r09bb998baee74a2c316446bd1a41ae7f8d7049d09d…
• lists.apache.org — https://lists.apache.org/thread.html/rc998b18880df98bafaade071346690c2bc1444adaa…
• lists.apache.org — https://lists.apache.org/thread.html/r03ee478b3dda3e381fd6189366fa7af97c980d2f60…
• lists.apache.org — https://lists.apache.org/thread.html/r9f93cf6dde308d42a9c807784e8102600d0397f5f8…
• lists.apache.org — https://lists.apache.org/thread.html/r3c5c3104813c1c5508b55564b66546933079250a46…
• lists.apache.org — https://lists.apache.org/thread.html/rcc44594d4d6579b90deccd4536b5d31f099ef563df…
• lists.apache.org — https://lists.apache.org/thread.html/rd336919f655b7ff309385e34a143e41c503e133da8…
• lists.apache.org — https://lists.apache.org/thread.html/r476d175be0aaf4a17680ef98c5153b4d336eaef76f…
• lists.apache.org — https://lists.apache.org/thread.html/r76142b8c5119df2178be7c2dba88fde552eedeec37…