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    CVE-2021-41773

    A flaw was found in a change made to path normalization in Apache HTTP Server 2.4.49. An attacker could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories are not protected by the usual default configuration "require all denied", these requests can succeed. If CGI scripts are also enabled for these aliased pathes, this could allow for remote code execution. This issue is known to be exploited in the wild. This issue only affects Apache 2.4.49 and not earlier versions. The fix in Apache HTTP Server 2.4.50 was found to be incomplete, see CVE-2021-42013.

    Published:Sep 29, 2021
    Last Modified:Feb 17, 2026
    EPS:Oct 5, 2021
    EPSS Score:0.94377
    CVSS Score:7.5

    CISA Notification

    Description

    A flaw was found in a change made to path normalization in Apache HTTP Server 2.4.49. An attacker could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories are not protected by the usual default configuration "require all denied", these requests can succeed. If CGI scripts are also enabled for these aliased pathes, this could allow for remote code execution. This issue is known to be exploited in the wild. This issue only affects Apache 2.4.49 and not earlier versions. The fix in Apache HTTP Server 2.4.50 was found to be incomplete, see CVE-2021-42013.

    Required Action:

    Apply updates per vendor instructions.

    Notes:

    No extra notes provided.

    Due Date
    Nov 17, 2021
    1759 days ago
    Alert Date
    Nov 3, 2021
    1773 days ago

    Affected Products

    Vendor
    Apache
    Product
    Http Server
    Vendor
    Fedoraproject
    Product
    Fedora
    Vendor
    Netapp
    Product
    Cloud Backup
    Vendor
    Oracle
    Product
    Instantis Enterprisetrack

    Exploits

    http://packetstormsecurity.com/files/164418/Apache-HTTP-Server-2.4.49-Path-Traversal-Remote-Code-Execution.htmlhttp://packetstormsecurity.com/files/164418/Apache-HTTP-Server-2.4.49-Path-Traversal.htmlhttp://packetstormsecurity.com/files/164629/Apache-2.4.49-2.4.50-Traversal-Remote-Code-Execution.htmlhttp://packetstormsecurity.com/files/164941/Apache-HTTP-Server-2.4.50-Remote-Code-Execution.htmlhttp://www.openwall.com/lists/oss-security/2021/10/08/1http://www.openwall.com/lists/oss-security/2021/10/08/3http://packetstormsecurity.com/files/164418/Apache-HTTP-Server-2.4.49-Path-Traversal-Remote-Code-Execution.htmlhttp://packetstormsecurity.com/files/164418/Apache-HTTP-Server-2.4.49-Path-Traversal.htmlhttp://packetstormsecurity.com/files/164629/Apache-2.4.49-2.4.50-Traversal-Remote-Code-Execution.htmlhttp://packetstormsecurity.com/files/164941/Apache-HTTP-Server-2.4.50-Remote-Code-Execution.htmlhttp://www.openwall.com/lists/oss-security/2021/10/08/1http://www.openwall.com/lists/oss-security/2021/10/08/3https://www.exploit-db.com/exploits/50383https://github.com/0xc4t/CVE-2021-41773https://github.com/0xGabe/Apache-CVEshttps://github.com/0xRar/CVE-2021-41773https://github.com/0xrogg/CVE-2021-41773https://github.com/12345qwert123456/CVE-2021-41773https://github.com/1nhann/CVE-2021-41773https://github.com/5gstudent/cve-2021-41773-and-cve-2021-42013https://github.com/a24ac1/CVE-2021-41773-PoChttps://github.com/abds059/APACHE-PATH-TRAVERSAL-RCE-CVE-2021-41773-https://github.com/abdulrafay25-svg/CVE-2021-41773-Exploithttps://github.com/adrianmafandy/CVE-2021-41773https://github.com/anldori/CVE-2021-41773-Scannerhttps://github.com/apapedulimu/Apachukhttps://github.com/aqiao-jashell/CVE-2021-41773https://github.com/aqiao-jashell/py-CVE-2021-41773https://github.com/Areeba-Zehra-Jafri/CVE-2021-41773---Apache-Path-Traversal---RCEhttps://github.com/ashique-thaha/CVE-2021-41773-POChttps://github.com/AssassinUKG/CVE-2021-41773https://github.com/AzkOsDev/CVE-2021-41773https://github.com/AzK-os-dev/CVE-2021-41773https://github.com/b1tsec/CVE-2021-41773https://github.com/BabyTeam1024/CVE-2021-41773https://github.com/belajarqywok/CVE-2021-41773-MSFhttps://github.com/bernardas/netsec-polygonhttps://github.com/blackn0te/Apache-HTTP-Server-2.4.49-2.4.50-Path-Traversal-Remote-Code-Executionhttps://github.com/blasty/CVE-2021-41773https://github.com/blu3ming/PoC-CVE-2021-41773https://github.com/BlueTeamSteve/CVE-2021-41773https://github.com/CalfCrusher/Path-traversal-RCE-Apache-2.4.49-2.4.50-Exploithttps://github.com/ch4os443/CVE-2021-41773https://github.com/ChanaPCN/CVE-2021-41773-Analysishttps://github.com/charanvoonna/CVE-2021-41773https://github.com/Chocapikk/CVE-2021-41773https://github.com/corelight/CVE-2021-41773https://github.com/creadpag/CVE-2021-41773-POChttps://github.com/CyberQuestor-infosec/CVE-2021-41773-Apache_2.4.49-Path-traversal-to-RCEhttps://github.com/DappaNISM/mass_cve-2021-41773https://github.com/dileepdkumar/LayarKacaSiber-CVE-2021-41773https://github.com/DoTuan1/Reserch-CVE-2021-41773https://github.com/dserdyk3-arch/Serdyuk-DO-homework-CVE-2021-41773https://github.com/EagleTube/CVE-2021-41773https://github.com/EkamSinghWalia/Mitigation-Apache-CVE-2021-41773-https://github.com/Emaar1x/CVE-2021-41773https://github.com/Fa1c0n35/CVE-2021-41773https://github.com/faizdotid/CVE-2021-41773https://github.com/FakesiteSecurity/CVE-2021-41773https://github.com/fnatalucci/CVE-2021-41773-RCEhttps://github.com/fxdyx-a/CVE-2021-41773-POChttps://github.com/gagaltotal/CVE-2021-41773-apachehttps://github.com/GlebUsalt/cybersecurity_portfoliohttps://github.com/gunzf0x/CVE-2021-41773https://github.com/Habib0x0/CVE-2021-41773https://github.com/habibiefaried/CVE-2021-41773-PoChttps://github.com/hackedrishi/CTF_WRITEUPS-TryHackMe-CVE-2021-41773-https://github.com/Hattan515/POC-CVE-2021-41773https://github.com/HightechSec/scarce-apache2https://github.com/honypot/CVE-2021-41773https://github.com/Hydragyrum/CVE-2021-41773-Playgroundhttps://github.com/i6c/MASS_CVE-2021-41773https://github.com/IcmpOff/Apache-2.4.49-2.4.50-Traversal-Remote-Code-Execution-Exploithttps://github.com/iilegacyyii/PoC-CVE-2021-41773https://github.com/im2sinister/CVE-2021-41773https://github.com/im-hanzou/apachrothttps://github.com/inbug-team/CVE-2021-41773_CVE-2021-42013https://github.com/iosifache/ApacheRCEEssayhttps://github.com/Iris288/CVE-2021-41773https://github.com/ISabbiI/PoC-Apache-CVE-2021-41773-Infrastructure-LABhttps://github.com/itsecurityco/CVE-2021-41773https://github.com/j4k0m/CVE-2021-41773https://github.com/javaamo/CVE-2021-41773https://github.com/jbovet/CVE-2021-41773https://github.com/jheeree/Simple-CVE-2021-41773-checkerhttps://github.com/JIYUN02/cve-2021-41773https://github.com/JKIM72403/CS4277-CVE-Path-Traversal-Apache-HTTP-Serverhttps://github.com/jkska23/Additive-Vulnerability-Analysis-CVE-2021-41773https://github.com/Joapath/CVE-2021-41773https://github.com/johnwickakash12/CVE-2021-41773https://github.com/justakazh/mass_cve-2021-41773https://github.com/khaidtraivch/CVE-2021-41773-Apache-2.4.49-https://github.com/klmntbelgium/cve-2021-41773-explorationhttps://github.com/knqyf263/CVE-2021-41773https://github.com/Kouf320/docker-lab-cve-2017-5638-cve-2021-41773https://github.com/ksanchezcld/httpd-2.4.49https://github.com/kubota/POC-CVE-2021-41773https://github.com/KunalKhandelwal-dev/cve-2021-41773-labhttps://github.com/KunalKhandelwal-dev/cve-2021-41773-source-code-analysishttps://github.com/LayarKacaSiber/CVE-2021-41773https://github.com/lheeeesoo/Apache-CVE-2021-41773https://github.com/lopqto/CVE-2021-41773_Honeypothttps://github.com/lorddemon/CVE-2021-41773-PoChttps://github.com/Ls4ss/CVE-2021-41773_CVE-2021-42013https://github.com/lucastran05/CVE-2021-41773https://github.com/LudovicPatho/CVE-2021-41773https://github.com/luongchivi/Preproduce-CVE-2021-41773https://github.com/m96dg/CVE-2021-41773-exercisehttps://github.com/mah4nzfr/CVE-2021-41773https://github.com/Mahfujurjust/CVE-2021-41773https://github.com/masahiro331/CVE-2021-41773https://github.com/MatanelGordon/docker-cve-2021-41773https://github.com/mauricelambert/CVE-2021-41773https://github.com/Maybe4a6f7365/CVE-2021-41773https://github.com/MazX0p/CVE-2021-41773https://github.com/mightysai1997/cve-2021-41773https://github.com/mightysai1997/CVE-2021-41773.git1https://github.com/mightysai1997/CVE-2021-41773hhttps://github.com/mightysai1997/CVE-2021-41773-i-https://github.com/mightysai1997/CVE-2021-41773-L-https://github.com/mightysai1997/CVE-2021-41773mhttps://github.com/mightysai1997/CVE-2021-41773-PoChttps://github.com/mightysai1997/CVE-2021-41773Shttps://github.com/mightysai1997/cve-2021-41773-v-https://github.com/mohwahyudi/cve-2021-41773https://github.com/MrCl0wnLab/SimplesApachePathTraversalhttps://github.com/mr-exo/CVE-2021-41773https://github.com/MuhammadHuzaifaAsif/security-labhttps://github.com/n3k00n3/CVE-2021-41773https://github.com/Nanxsec/exploitApachehttps://github.com/ninthsgrsj-source/vulhub-apachehttps://github.com/noflowpls/CVE-2021-41773https://github.com/norrig/CVE-2021-41773-exploiterhttps://github.com/numanturle/CVE-2021-41773https://github.com/OfriOuzan/CVE-2021-41773_CVE-2021-42013_Exploitshttps://github.com/orangmuda/CVE-2021-41773https://github.com/Park123r/CVE-2021-41773https://github.com/PentesterGuruji/CVE-2021-41773https://github.com/pirenga/CVE-2021-41773https://github.com/pisut4152/Sigma-Rule-for-CVE-2021-41773-and-CVE-2021-42013-exploitation-attempthttps://github.com/Plunder283/CVE-2021-41773https://github.com/psibot/apache-vulnerablehttps://github.com/puckiestyle/CVE-2021-41773https://github.com/pwn3z/CVE-2021-41773-Apache-RCEhttps://github.com/r00tVen0m/CVE-2021-41773https://github.com/r0otk3r/CVE-2021-41773https://github.com/ranggaggngntt/CVE-2021-41773https://github.com/redspy-sec/CVE-2021-41773https://github.com/retrymp3/apache2.4.49VulnerableLabSetuphttps://github.com/RevShellXD/LFI-Destructionhttps://github.com/RizqiSec/CVE-2021-41773https://github.com/s-amnajafri/CVE-2021-41773-Apache-Labhttps://github.com/SANR01/CVE-2021-41773-Exploit-Labhttps://github.com/Shams-Ul-Mehmood/CVE-2021-41773-Exploithttps://github.com/shellreaper/CVE-2021-41773https://github.com/shiomiyan/CVE-2021-41773https://github.com/sixpacksecurity/CVE-2021-41773https://github.com/skentagon/CVE-2021-41773https://github.com/snapdowgg/CVE-2021-41773https://github.com/sobanahmed6061/CVE-2021-41773-RedTeamhttps://github.com/Soliux/CVE-2021-41773https://github.com/sudo0xksh/cve-2021-41773-checkerhttps://github.com/superzerosec/CVE-2021-41773https://github.com/TAI-REx/cve-2021-41773-nsehttps://github.com/Taldrid1/cve-2021-41773https://github.com/thehackersbrain/CVE-2021-41773https://github.com/TheKernelPanic/exploit-apache2-cve-2021-41773https://github.com/TheLastVvV/CVE-2021-41773https://github.com/theLSA/apache-httpd-path-traversal-checkerhttps://github.com/tiemio/SSH-key-and-RCE-PoC-for-CVE-2021-41773https://github.com/TishcaTpx/POC-CVE-2021-41773https://github.com/tr3m0x/CVE-2021-41773https://github.com/tsiddiquea/cve-reproduction-labhttps://github.com/twseptian/cve-2021-41773https://github.com/twseptian/cve-2021-41773-docker-labhttps://github.com/Vanshuk-Bhagat/Apache-HTTP-Server-Vulnerabilities-CVE-2021-41773-and-CVE-2021-42013https://github.com/vida003/Scanner-CVE-2021-41773https://github.com/vinhjaxt/CVE-2021-41773-exploithttps://github.com/Vulnmachines/cve-2021-41773https://github.com/vuongnv3389-sec/cve-2021-41773https://github.com/walnutsecurity/cve-2021-41773https://github.com/wangfly-me/Apache_Penetration_Toolhttps://github.com/wolf1892/CVE-2021-41773https://github.com/xMohamed0/CVE-2021-41773https://github.com/Zeop-CyberSec/apache_normalize_pathhttps://github.com/ZephrFish/CVE-2021-41773-PoChttps://github.com/zer0qs/CVE-2021-41773https://github.com/zerodaywolf/CVE-2021-41773_42013https://github.com/zeronine9/CVE-2021-41773https://github.com/zubairahm3d/apache-cve-2021-41773-labhttps://github.com/Zyx2440/Apache-HTTP-Server-2.4.50-RCEhttps://www.exploit-db.com/exploits/50512

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    References

    http://packetstormsecurity.com/files/164418/Apache-HTTP-Server-2.4.49-Path-Traversal-Remote-Code-Execution.html
    http://packetstormsecurity.com/files/164418/Apache-HTTP-Server-2.4.49-Path-Traversal.html
    http://packetstormsecurity.com/files/164629/Apache-2.4.49-2.4.50-Traversal-Remote-Code-Execution.html
    http://packetstormsecurity.com/files/164941/Apache-HTTP-Server-2.4.50-Remote-Code-Execution.html
    http://www.openwall.com/lists/oss-security/2021/10/05/2
    http://www.openwall.com/lists/oss-security/2021/10/07/1
    http://www.openwall.com/lists/oss-security/2021/10/07/6
    http://www.openwall.com/lists/oss-security/2021/10/08/1
    http://www.openwall.com/lists/oss-security/2021/10/08/2
    http://www.openwall.com/lists/oss-security/2021/10/08/3
    http://www.openwall.com/lists/oss-security/2021/10/08/4
    http://www.openwall.com/lists/oss-security/2021/10/08/5
    http://www.openwall.com/lists/oss-security/2021/10/08/6
    http://www.openwall.com/lists/oss-security/2021/10/09/1
    http://www.openwall.com/lists/oss-security/2021/10/11/4
    http://www.openwall.com/lists/oss-security/2021/10/15/3
    http://www.openwall.com/lists/oss-security/2021/10/16/1
    https://httpd.apache.org/security/vulnerabilities_24.html
    https://lists.apache.org/thread.html/r17a4c6ce9aff662efd9459e9d1850ab4a611cb23392fc68264c72cb3%40%3Ccvs.httpd.apache.org%3E
    https://lists.apache.org/thread.html/r6abf5f2ba6f1aa8b1030f95367aaf17660c4e4c78cb2338aee18982f%40%3Cusers.httpd.apache.org%3E
    https://lists.apache.org/thread.html/r7c795cd45a3384d4d27e57618a215b0ed19cb6ca8eb070061ad5d837%40%3Cannounce.apache.org%3E
    https://lists.apache.org/thread.html/r98d704ed4377ed889d40479db79ed1ee2f43b2ebdd79ce84b042df45%40%3Cannounce.apache.org%3E
    https://lists.apache.org/thread.html/rb5b0e46f179f60b0c70204656bc52fcb558e961cb4d06a971e9e3efb%40%3Cusers.httpd.apache.org%3E
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RMIIEFINL6FUIOPD2A3M5XC6DH45Y3CC/
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WS5RVHOIIRECG65ZBTZY7IEJVWQSQPG3/
    https://security.gentoo.org/glsa/202208-20
    https://security.netapp.com/advisory/ntap-20211029-0009/
    https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-pathtrv-LAzg68cZ
    https://www.oracle.com/security-alerts/cpujan2022.html
    http://packetstormsecurity.com/files/164418/Apache-HTTP-Server-2.4.49-Path-Traversal-Remote-Code-Execution.html
    http://packetstormsecurity.com/files/164418/Apache-HTTP-Server-2.4.49-Path-Traversal.html
    http://packetstormsecurity.com/files/164629/Apache-2.4.49-2.4.50-Traversal-Remote-Code-Execution.html
    http://packetstormsecurity.com/files/164941/Apache-HTTP-Server-2.4.50-Remote-Code-Execution.html
    http://www.openwall.com/lists/oss-security/2021/10/05/2
    http://www.openwall.com/lists/oss-security/2021/10/07/1
    http://www.openwall.com/lists/oss-security/2021/10/07/6
    http://www.openwall.com/lists/oss-security/2021/10/08/1
    http://www.openwall.com/lists/oss-security/2021/10/08/2
    http://www.openwall.com/lists/oss-security/2021/10/08/3
    http://www.openwall.com/lists/oss-security/2021/10/08/4
    http://www.openwall.com/lists/oss-security/2021/10/08/5
    http://www.openwall.com/lists/oss-security/2021/10/08/6
    http://www.openwall.com/lists/oss-security/2021/10/09/1
    http://www.openwall.com/lists/oss-security/2021/10/11/4
    http://www.openwall.com/lists/oss-security/2021/10/15/3
    http://www.openwall.com/lists/oss-security/2021/10/16/1
    https://httpd.apache.org/security/vulnerabilities_24.html
    https://lists.apache.org/thread.html/r17a4c6ce9aff662efd9459e9d1850ab4a611cb23392fc68264c72cb3%40%3Ccvs.httpd.apache.org%3E
    https://lists.apache.org/thread.html/r6abf5f2ba6f1aa8b1030f95367aaf17660c4e4c78cb2338aee18982f%40%3Cusers.httpd.apache.org%3E
    https://lists.apache.org/thread.html/r7c795cd45a3384d4d27e57618a215b0ed19cb6ca8eb070061ad5d837%40%3Cannounce.apache.org%3E
    https://lists.apache.org/thread.html/r98d704ed4377ed889d40479db79ed1ee2f43b2ebdd79ce84b042df45%40%3Cannounce.apache.org%3E
    https://lists.apache.org/thread.html/rb5b0e46f179f60b0c70204656bc52fcb558e961cb4d06a971e9e3efb%40%3Cusers.httpd.apache.org%3E
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RMIIEFINL6FUIOPD2A3M5XC6DH45Y3CC/
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WS5RVHOIIRECG65ZBTZY7IEJVWQSQPG3/
    https://security.gentoo.org/glsa/202208-20
    https://security.netapp.com/advisory/ntap-20211029-0009/
    https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-pathtrv-LAzg68cZ
    https://www.oracle.com/security-alerts/cpujan2022.html
    https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-41773

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High