Description
In Apache HTTP server 2.4.0 to 2.4.39, Redirects configured with mod_rewrite that were intended to be self-referential might be fooled by encoded newlines and redirect instead to an unexpected URL within the request URL.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | Apache HTTP Server | 2.4.0 to 2.4.39 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | apache2 | 2.4.41-1 | — |
| Debian 13 | apache2 | 2.4.41-1 | — |
| Debian 12 | apache2 | 2.4.41-1 | — |
| Debian 10 | apache2 | 2.4.38-3+deb10u1 | DSA-4509-1 |
| Debian 9 | apache2 | 2.4.25-3+deb9u8 | DSA-4509-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 8 | apache2 | 2.4.10-10+deb8u15 | DLA-1900-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | apache2 | 2.4.41-1ubuntu1 | — |
| Ubuntu 18.04 LTS | apache2 | 2.4.29-1ubuntu4.10 | USN-4113-1 |
| Ubuntu 16.04 LTS | apache2 | 2.4.18-2ubuntu3.12 | USN-4113-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 14.04 LTS | apache2 | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | httpd +6 | 2.4.37-30.module+el8.3.0+7001+0766b9e7 | RHSA-2020:4751 |
| RHEL 8 | mod_http2 | 1.15.7-2.module+el8.3.0+7670+8bf57d29 | RHSA-2020:4751 |
| RHEL 8 | mod_md | 1:2.0.8-8.module+el8.3.0+6814+67d1e611 | RHSA-2020:4751 |
| RHEL 8 | mod_ssl +1 | 1:2.4.37-30.module+el8.3.0+7001+0766b9e7 | RHSA-2020:4751 |
| RHEL 7 | httpd +5 | 2.4.6-95.el7 | RHSA-2020:3958 |
| RHEL 7 | mod_ssl +1 | 1:2.4.6-95.el7 | RHSA-2020:3958 |
| RHEL 3 | httpd24-httpd +5 | 2.4.34-18.el6 | RHSA-2020:2263 |
| RHEL 3 | httpd24-mod_md | 1:2.0.8-1.el7 | RHSA-2020:2263 |
| RHEL 3 | httpd24-mod_ssl +1 | 1:2.4.34-18.el6 | RHSA-2020:2263 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat JBoss Core Services 1 | jbcs-httpd24-apr +1 | 1.6.3-86.jbcs.el6 | RHSA-2020:1337 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-brotli +1 | 1.0.6-21.jbcs.el6 | RHSA-2020:1337 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-httpd +6 | 2.4.37-52.jbcs.el6 | RHSA-2020:1337 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-mod_cluster-native | 1.3.12-41.Final_redhat_2.jbcs.el6 | RHSA-2020:1337 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-mod_http2 | 1.11.3-22.jbcs.el6 | RHSA-2020:1337 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-mod_ssl +1 | 1:2.4.37-52.jbcs.el6 | RHSA-2020:1337 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-openssl +4 | 1:1.1.1c-16.jbcs.el6 | RHSA-2020:1337 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 8 | mod_md | 1:2.0.8-8.module_el8.5.0+2609+b30d9eec | ALSA-2020:4751 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | mod_md | 1:2.0.8-8.module+el8.4.0+553+7a69454b | RLSA-2020:4751 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP1 | apache2 | 2.4.33-3.21.1 | SUSE-SU-2019:2237-1 |
| SLES 15 | apache2 | 2.4.33-3.21.1 | SUSE-SU-2019:2237-1 |
| SLES 12 SP4 | apache2 | 2.4.23-29.43.1 | SUSE-SU-2019:2329-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP4 | apache2 | 2.4.23-29.43.1 | SUSE-SU-2019:2329-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | apache2 | 2.4.49-1.1 | openSUSE-SU-2024:10623-1 |
| openSUSE Leap 15.1 | apache2 | 2.4.33-lp151.8.6.1 | openSUSE-SU-2019:2051-1 |
| openSUSE Leap 15.0 | apache2 | 2.4.33-lp151.8.6.1 | openSUSE-SU-2019:2051-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | apache2 | 2.4.41-r0 | — |
| Alpine v3.23 | apache2 | 2.4.41-r0 | — |
| Alpine v3.22 | apache2 | 2.4.41-r0 | — |
| Alpine v3.21 | apache2 | 2.4.41-r0 | — |
| Alpine v3.20 | apache2 | 2.4.41-r0 | — |
Show 13 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | apache2 | 2.4.41-r0 | — |
| Alpine v3.18 | apache2 | 2.4.41-r0 | — |
| Alpine v3.17 | apache2 | 2.4.41-r0 | — |
| Alpine v3.16 | apache2 | 2.4.41-r0 | — |
| Alpine v3.15 | apache2 | 2.4.41-r0 | — |
| Alpine v3.14 | apache2 | 2.4.41-r0 | — |
| Alpine v3.13 | apache2 | 2.4.41-r0 | — |
| Alpine v3.12 | apache2 | 2.4.41-r0 | — |
| Alpine v3.11 | apache2 | 2.4.41-r0 | — |
| Alpine v3.10 | apache2 | 2.4.41-r0 | — |
| Alpine v3.9 | apache2 | 2.4.41-r0 | — |
| Alpine v3.8 | apache2 | 2.4.41-r0 | — |
| Alpine v3.7 | apache2 | 2.4.41-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | httpd +7 | 2.4.41-1.amzn2.0.1 | ALAS2-2019-1341 |
| Amazon Linux 2 | mod_ssl +1 | 1:2.4.41-1.amzn2.0.1 | ALAS2-2019-1341 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | httpd +6 | 2.4.37-30.0.1.module+el8.3.0+7816+49791cfd | ELSA-2020-4751 |
| Oracle Linux 8 | mod_http2 | 1.15.7-2.module+el8.3.0+7816+49791cfd | ELSA-2020-4751 |
| Oracle Linux 8 | mod_md | 1:2.0.8-8.module+el8.3.0+7816+49791cfd | ELSA-2020-4751 |
| Oracle Linux 8 | mod_ssl +1 | 1:2.4.37-30.0.1.module+el8.3.0+7816+49791cfd | ELSA-2020-4751 |
| Oracle Linux 7 | httpd +5 | 2.4.6-95.0.1.el7 | ELSA-2020-3958 |
| Oracle Linux 7 | mod_ssl +1 | 1:2.4.6-95.0.1.el7 | ELSA-2020-3958 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
Exploit-DB 1
- Apache Httpd mod_rewrite - Open Redirects EDB-47689 · webapps · Oct 14, 2019
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Automated scanner template
A ready-made Nuclei template detects this vulnerability automatically. Vulnerabilities with public scanner templates are typically probed across the internet soon after the template appears — exposed systems should be patched first.
- Apache HTTP server v2.4.0 to v2.4.39 - Open Redirect http/cves/2019/CVE-2019-10098.yaml
Source: projectdiscovery/nuclei-templates (MIT) — updated daily. Only links are listed.
Advisories 17
- ALSA-2020:4751 Moderate: httpd:2.4 security, bug fix, and enhancement update AlmaLinux Security Advisories · Nov 2, 2026
- RHSA-2020:4751 Red Hat Security Advisory: httpd:2.4 security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Sep 21, 2026
- RHSA-2020:3958 Red Hat Security Advisory: httpd security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Sep 21, 2026
- RHSA-2020:2263 Red Hat Security Advisory: httpd24-httpd and httpd24-mod_md security and enhancement update Red Hat Security Advisories (RHSA) · Sep 21, 2026
- RHSA-2020:1337 Red Hat Security Advisory: Red Hat JBoss Core Services Apache HTTP Server 2.4.37 SP2 security update Red Hat Security Advisories (RHSA) · Sep 21, 2026
- USN-4113-1 apache2 vulnerabilities Ubuntu Security Notices (USN) · Apr 27, 2026
- DSA-4509-1 apache2 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1900-1 apache2 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- RLSA-2020:4751 Moderate: httpd:2.4 security, bug fix, and enhancement update Rocky Linux Security Advisories · Feb 5, 2026
- openSUSE-SU-2019:2051-1 Security update for apache2 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:2237-1 Security update for apache2 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:2329-1 Security update for apache2 SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10623-1 apache2-2.4.49-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2024-1591 Juniper JUNOS: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 11, 2024
- ELSA-2020-4751 Moderate: httpd:2.4 security, bug fix, and enhancement update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Nov 10, 2020
- ELSA-2020-3958 Moderate: httpd security, bug fix, and enhancement update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Oct 6, 2020
- ALAS2-2019-1341 Moderate: httpd security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Oct 30, 2019
References
- [oss-security] 20200401 CVE-2020-1927: mod_rewrite configurations vulnerable to open redirect mailing-list
- [httpd-cvs] 20200401 svn commit: r1058586 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilit mailing-list
- [httpd-cvs] 20200401 svn commit: r1058587 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilit mailing-list
- [httpd-cvs] 20200420 svn commit: r1876764 - /httpd/httpd/branches/2.4.x/CHANGES mailing-list
- https://www.oracle.com/security-alerts/cpuapr2020.html
- https://www.oracle.com/technetwork/security-advisory/cpuoct2019-5072832.html
- https://www.oracle.com/security-alerts/cpujan2020.html
- https://httpd.apache.org/security/vulnerabilities_24.html
- [httpd-cvs] 20210330 svn commit: r1073139 [1/13] - in /websites/staging/httpd/trunk/content: ./ security/json/ mailing-list
- [httpd-cvs] 20210330 svn commit: r1073143 [3/3] - in /websites/staging/httpd/trunk/content: ./ security/ mailing-list
- [httpd-cvs] 20210330 svn commit: r1073140 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/cvejsontohtml.py security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.ht mailing-list
- [httpd-cvs] 20210330 svn commit: r1073139 [12/13] - in /websites/staging/httpd/trunk/content: ./ security/json/ mailing-list
- [httpd-cvs] 20210330 svn commit: r1888194 [12/13] - /httpd/site/trunk/content/security/json/ mailing-list
- [httpd-cvs] 20210330 svn commit: r1073149 [1/13] - in /websites/staging/httpd/trunk/content: ./ security/ security/json/ mailing-list
- [httpd-cvs] 20210330 svn commit: r1073149 [13/13] - in /websites/staging/httpd/trunk/content: ./ security/ security/json/ mailing-list
- [httpd-cvs] 20210606 svn commit: r1075470 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/json/CVE-2020-13938.json security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabiliti mailing-list
- https://www.oracle.com/security-alerts/cpuApr2021.html