CVE-2021-22876: Infoleak

Published Mar 23, 2021
·
Updated

curl 7.1.1 to and including 7.75.0 is vulnerable to an "Exposure of Private Personal Information to an Unauthorized Actor" by leaking credentials in the HTTP Referer: header. libcurl does not strip off user credentials from the URL when automatically populating the Referer: HTTP request header field in outgoing HTTP requests, and therefore risks leaking sensitive data to the server that is the target of the second HTTP request.

Other sources

cURL libcurl could allow a remote attacker to obtain sensitive information, caused by the failure to strip off user credentials from the URL when automatically populating the Referer: HTTP request header field in outgoing HTTP requests. By sending a specially-crafted HTTP request, an attacker could exploit this vulnerability to obtain user credentials, and use this information to launch further attacks against the affected system.

— IBM

It was discovered that libcurl did not remove authentication credentials from URLs when automatically populating the Referer HTTP request header while handling HTTP redirects. This could lead to exposure of the credentials to the server to which requests were redirected.

libcurl does not strip off user credentials from the URL when automatically populating the Referer: HTTP request header field in outgoing HTTP requests, and therefore risks leaking sensitive data to the server that is the target of the second HTTP request.

Upstream Advisory:

https://curl.se/docs/CVE-2021-22876.html

— Red Hat

Affected Software

40 affected componentsFixes available
redhat/jbcs-httpd24<0:1-18.el8
0:1-18.el8
redhat/jbcs-httpd24-apr<0:1.6.3-105.el8
0:1.6.3-105.el8
redhat/jbcs-httpd24-apr-util<0:1.6.1-82.el8
0:1.6.1-82.el8
redhat/jbcs-httpd24-brotli<0:1.0.6-40.el8
0:1.0.6-40.el8
redhat/jbcs-httpd24-curl<0:7.77.0-2.el8
0:7.77.0-2.el8
redhat/jbcs-httpd24-httpd<0:2.4.37-74.el8
0:2.4.37-74.el8
redhat/jbcs-httpd24-jansson<0:2.11-55.el8
0:2.11-55.el8
redhat/jbcs-httpd24-nghttp2<0:1.39.2-37.el8
0:1.39.2-37.el8
redhat/jbcs-httpd24-openssl<1:1.1.1g-6.el8
1:1.1.1g-6.el8
redhat/jbcs-httpd24-openssl-chil<0:1.0.0-5.el8
0:1.0.0-5.el8
redhat/jbcs-httpd24-openssl-pkcs11<0:0.4.10-20.el8
0:0.4.10-20.el8
redhat/jbcs-httpd24<0:1-18.jbcs.el7
0:1-18.jbcs.el7
redhat/jbcs-httpd24-apr<0:1.6.3-105.jbcs.el7
0:1.6.3-105.jbcs.el7
redhat/jbcs-httpd24-apr-util<0:1.6.1-82.jbcs.el7
0:1.6.1-82.jbcs.el7
redhat/jbcs-httpd24-curl<0:7.77.0-2.jbcs.el7
0:7.77.0-2.jbcs.el7
redhat/jbcs-httpd24-httpd<0:2.4.37-74.jbcs.el7
0:2.4.37-74.jbcs.el7
redhat/jbcs-httpd24-jansson<0:2.11-55.jbcs.el7
0:2.11-55.jbcs.el7
redhat/rh-dotnet31-curl<0:7.61.1-22.el7_9
0:7.61.1-22.el7_9
redhat/curl<0:7.61.1-22.el8
0:7.61.1-22.el8
debian/curl
7.64.0-4+deb10u27.64.0-4+deb10u77.74.0-1.3+deb11u97.74.0-1.3+deb11u107.88.1-10+deb12u37.88.1-10+deb12u48.4.0-2
redhat/curl<7.76.0
7.76.0
IBM QRadar SIEM<=7.5.0 GA
IBM QRadar SIEM<=7.4.3 GA - 7.4.3 FP4
IBM QRadar SIEM<=7.3.3 GA - 7.3.3 FP10
haxx libcurl>=7.1.1<=7.75.0
Fedoraproject Fedora=32
Fedoraproject Fedora=33
Fedoraproject Fedora=34
NetApp Hci Management Node
NetApp Solidfire
NetApp Hci Compute Node
NetApp Hci Storage Node
Broadcom Fabric Operating System
Debian Debian Linux=9.0
Siemens Sinec Infrastructure Network Services<1.0.1.1
Oracle Communications Billing and Revenue Management=12.0.0.3.0
Oracle Essbase=21.2
Splunk Universal Forwarder>=8.2.0<8.2.12
Splunk Universal Forwarder>=9.0.0<9.0.6
Splunk Universal Forwarder=9.1.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/jbcs-httpd24 to a version that resolves this vulnerability.

    Fixed in 0:1-18.el8
  2. Upgrade

    Upgrade redhat/jbcs-httpd24-apr to a version that resolves this vulnerability.

    Fixed in 0:1.6.3-105.el8
  3. Upgrade

    Upgrade redhat/jbcs-httpd24-apr-util to a version that resolves this vulnerability.

    Fixed in 0:1.6.1-82.el8
  4. Upgrade

    Upgrade redhat/jbcs-httpd24-brotli to a version that resolves this vulnerability.

    Fixed in 0:1.0.6-40.el8
  5. Upgrade

    Upgrade redhat/jbcs-httpd24-curl to a version that resolves this vulnerability.

    Fixed in 0:7.77.0-2.el8
  6. Upgrade

    Upgrade redhat/jbcs-httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.37-74.el8
  7. Upgrade

    Upgrade redhat/jbcs-httpd24-jansson to a version that resolves this vulnerability.

    Fixed in 0:2.11-55.el8
  8. Upgrade

    Upgrade redhat/jbcs-httpd24-nghttp2 to a version that resolves this vulnerability.

    Fixed in 0:1.39.2-37.el8
  9. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl to a version that resolves this vulnerability.

    Fixed in 1:1.1.1g-6.el8
  10. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl-chil to a version that resolves this vulnerability.

    Fixed in 0:1.0.0-5.el8
  11. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl-pkcs11 to a version that resolves this vulnerability.

    Fixed in 0:0.4.10-20.el8
  12. Upgrade

    Upgrade redhat/jbcs-httpd24 to a version that resolves this vulnerability.

    Fixed in 0:1-18.jbcs.el7
  13. Upgrade

    Upgrade redhat/jbcs-httpd24-apr to a version that resolves this vulnerability.

    Fixed in 0:1.6.3-105.jbcs.el7
  14. Upgrade

    Upgrade redhat/jbcs-httpd24-apr-util to a version that resolves this vulnerability.

    Fixed in 0:1.6.1-82.jbcs.el7
  15. Upgrade

    Upgrade redhat/jbcs-httpd24-curl to a version that resolves this vulnerability.

    Fixed in 0:7.77.0-2.jbcs.el7
  16. Upgrade

    Upgrade redhat/jbcs-httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.37-74.jbcs.el7
  17. Upgrade

    Upgrade redhat/jbcs-httpd24-jansson to a version that resolves this vulnerability.

    Fixed in 0:2.11-55.jbcs.el7
  18. Upgrade

    Upgrade redhat/rh-dotnet31-curl to a version that resolves this vulnerability.

    Fixed in 0:7.61.1-22.el7_9
  19. Upgrade

    Upgrade redhat/curl to a version that resolves this vulnerability.

    Fixed in 0:7.61.1-22.el8
  20. Upgrade

    Upgrade debian/curl to a version that resolves this vulnerability.

    Fixed in 7.64.0-4+deb10u2Fixed in 7.64.0-4+deb10u7Fixed in 7.74.0-1.3+deb11u9Fixed in 7.74.0-1.3+deb11u10Fixed in 7.88.1-10+deb12u3Fixed in 7.88.1-10+deb12u4Fixed in 8.4.0-2
  21. Upgrade

    Upgrade redhat/curl to a version that resolves this vulnerability.

    Fixed in 7.76.0
  22. Configuration

    Do not enable automatic Referer generation when following redirects. Avoid curl -e ';auto' or --referer ';auto', and do not enable libcurl CURLOPT_AUTOREFERER.

    curl command line tool / libcurl automatic Referer generation on redirects = disabled
  23. Configuration

    Do not include credentials in URLs such as https://username:password@example.com. For curl, use -u or --user; for libcurl, use CURLOPT_USERPWD or CURLOPT_USERNAME / CURLOPT_PASSWORD.

    curl command line tool / libcurl authentication credential placement = credentials supplied through options, not URLs

Event History

Mar 23, 2021
Data Sourced
via Red Hat·10:06 AM
DescriptionSeverityAffected Software
Mar 31, 2021
CVE Published
12:00 AM
Apr 1, 2021
CVE Published
via MITRE·05:45 PM
Data Sourced
via MITRE·05:45 PM
DescriptionWeakness
Data Sourced
via NVD·06:15 PM
RemedyDescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the vulnerability ID of this vulnerability?

The vulnerability ID is CVE-2021-22876.

2

What is the severity of CVE-2021-22876?

The severity of CVE-2021-22876 is high with a severity value of 7.5.

3

How does CVE-2021-22876 affect libcurl?

CVE-2021-22876 affects libcurl by allowing a remote attacker to obtain sensitive information.

4

How can an attacker exploit CVE-2021-22876?

An attacker can exploit CVE-2021-22876 by sending a specially-crafted HTTP request.

5

Is there a fix available for CVE-2021-22876?

Yes, a fix is available for CVE-2021-22876. Please refer to the provided references for more information on how to obtain the fix.

Company

Resources

Contact

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