CVE-2020-1760

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Last Modified: UTC

Moderate Moderate Impact What does this mean?
5.8 CVSS v3 Base Score

Description

A flaw was found in the Ceph Object Gateway, where it supports request sent by an anonymous user in Amazon S3. This flaw could lead to potential XSS attacks due to the lack of proper neutralization of untrusted input.

Statement

Red Hat OpenStack Platform 15 (RHOSP) packages Ceph but no longer uses it, instead pulling ceph directly from the Red Hat Ceph Storage 4 repository. For this reason, RHOSP will not be updated for this flaw.

This issue affects the versions of ceph as shipped with Red Hat Ceph Storage 3, 4 and Red Hat Openshift Container Storage 4.2 as it allows unauthenticated requests sent by an anonymous user for Amazon S3.

Mitigation

* Mitigation provided by DigitalOcean:

Mitigation relies on the HAProxy load-balancers in front of RGW, and uses HAProxy ACLs combined with in-house Lua embedded in HAProxy.

1. Detect usage of the query-parameters without any signature (either pre-signed or header), and return S3-formatted error.
2. Validate the content in the query-parameters, return S3-formatted error.

HAProxy mitigation:
===
acl req_s3_GetObject REDACTED ## redacted uses internal Lua to detect GetObject
acl has_accesskey REDACTED ## redacted uses internal Lua to detect & validate signature

# detection 1, QPs present
acl req_s3_GetObject_urlp_response url_param(response-cache-control) -m found
acl req_s3_GetObject_urlp_response url_param(response-expires) -m found
acl req_s3_GetObject_urlp_response url_param(response-content-disposition) -m found
acl req_s3_GetObject_urlp_response url_param(response-content-encoding) -m found
acl req_s3_GetObject_urlp_response url_param(response-content-language) -m found
acl req_s3_GetObject_urlp_response url_param(response-content-type) -m found

# detection 2, QPs containing unprintable ascii incl CRLR
acl req_s3_GetObject_urlp_response_crlf url_param(response-cache-control) -m sub -i %00 %01 %02 %03 %04 %05 %06 %07 %08 %09 %0a %0b %0c %0d %0e %0f %10 %11 %12 %13 %14 %15 %16 %17 %18 %19 %1a %1b %1c %1d %1e %1f
acl req_s3_GetObject_urlp_response_crlf url_param(response-expires) -m sub -i %00 %01 %02 %03 %04 %05 %06 %07 %08 %09 %0a %0b %0c %0d %0e %0f %10 %11 %12 %13 %14 %15 %16 %17 %18 %19 %1a %1b %1c %1d %1e %1f
acl req_s3_GetObject_urlp_response_crlf url_param(response-content-disposition) -m sub -i %00 %01 %02 %03 %04 %05 %06 %07 %08 %09 %0a %0b %0c %0d %0e %0f %10 %11 %12 %13 %14 %15 %16 %17 %18 %19 %1a %1b %1c %1d %1e %1f
acl req_s3_GetObject_urlp_response_crlf url_param(response-content-encoding) -m sub -i %00 %01 %02 %03 %04 %05 %06 %07 %08 %09 %0a %0b %0c %0d %0e %0f %10 %11 %12 %13 %14 %15 %16 %17 %18 %19 %1a %1b %1c %1d %1e %1f
acl req_s3_GetObject_urlp_response_crlf url_param(response-content-language) -m sub -i %00 %01 %02 %03 %04 %05 %06 %07 %08 %09 %0a %0b %0c %0d %0e %0f %10 %11 %12 %13 %14 %15 %16 %17 %18 %19 %1a %1b %1c %1d %1e %1f
acl req_s3_GetObject_urlp_response_crlf url_param(response-content-type) -m sub -i %00 %01 %02 %03 %04 %05 %06 %07 %08 %09 %0a %0b %0c %0d %0e %0f %10 %11 %12 %13 %14 %15 %16 %17 %18 %19 %1a %1b %1c %1d %1e %1f

# block for detection 1
http-request use-service lua.REDACTED if req_s3_GetObject req_s3_GetObject_urlp_response !has_accesskey

# block for detection 2
http-request use-service lua.REDACTED if req_s3_GetObject req_s3_GetObject_urlp_response_crlf
===

Additional Information

External References

Content from www.cve.org is not included.https://www.cve.org/CVERecord?id=CVE-2020-1760

Content from nvd.nist.gov is not included.https://nvd.nist.gov/vuln/detail/CVE-2020-1760

Content from www.openwall.com is not included.https://www.openwall.com/lists/oss-security/2020/04/07/1

Affected Packages and Issued Red Hat Security Errata

Products / Services Components State Errata
Red Hat Ceph Storage 2 ceph Out of support scope
Red Hat Ceph Storage 3 ceph Affected
Red Hat Ceph Storage 4.1 ceph Fixed RHSA-2020:3003
Red Hat Ceph Storage 4.1 ceph-ansible Fixed RHSA-2020:3003
Red Hat Ceph Storage 4.1 ceph-medic Fixed RHSA-2020:3003
Red Hat Ceph Storage 4.1 cockpit-ceph-installer Fixed RHSA-2020:3003
Red Hat Ceph Storage 4.1 nfs-ganesha Fixed RHSA-2020:3003
Red Hat Enterprise Linux 8 ceph Not affected
Red Hat OpenStack Platform 13 (Queens) ceph Not affected
Red Hat OpenStack Platform 15 (Stein) ceph Will not fix
Unless explicitly stated as not affected, all previous versions of packages in any minor update stream of a product listed here should be assumed vulnerable, although may not have been subject to full analysis.

Common Vulnerability Scoring System (CVSS) Score Details

Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authorities (CNA) source for its products and services (see Red Hat classifications ).

CVSS v3 Score Breakdown Red Hat NVD
CVSS v3 Base Score 5.8 6.1
Attack Vector Network Network
Attack Complexity High Low
Privileges Required None None
User Interaction Required Required
Scope Changed Changed
Confidentiality Impact Low Low
Integrity Impact Low Low
Availability Impact Low None

CVSS v3 Vector

Red Hat CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:L

NVD CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Acknowledgements

Red Hat would like to thank Robin H. Johnson (DigitalOcean) for reporting this issue. Upstream acknowledges William Bowling as the original reporter.

Frequently Asked Questions

Why is Red Hat's CVSS v3 score or Impact different from other vendors?

 For open source software shipped by multiple vendors, the CVSS base scores may vary for each vendor's version depending on the version they ship, how they ship it, the platform, and even how the software is compiled. This makes scoring of vulnerabilities difficult for third-party vulnerability databases such as NVD that only provide a single CVSS base score for each vulnerability. Red Hat scores reflect how a vulnerability affects our products specifically.

For more information, see https://access.redhat.com/solutions/762393.

My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?
  • "Under investigation" doesn't necessarily mean that the product is affected by this vulnerability. It only means that our Analysis Team is still working on determining whether the product is affected and how it is affected.
  • "Affected" means that our Analysis Team has determined that this product is affected by this vulnerability and might release a fix to address this in the near future.

What can I do if my product is listed as "Will not fix"?

 A "will not fix" status means that a fix for an affected product version is not planned or not possible due to complexity, which may create additional risk.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Upgrade to a supported product version that includes a fix for this vulnerability (recommended).
  • Apply a mitigation (if one exists).
  • Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.

What can I do if my product is listed as "Fix deferred"?

 A deferred status means that a fix for an affected product version is not guaranteed due to higher-priority development work.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Apply a mitigation (if one exists).
  • Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
  • Red Hat Engineering focuses on addressing high-priority issues based on their complexity or limited lifecycle support. Therefore, lower-priority issues will not receive immediate fixes.

What is a mitigation?

 A mitigation is an action that can be taken to reduce the impact of a security vulnerability, without deploying any fixes.

I have a Red Hat product but it is not in the above list, is it affected?

 The listed products were found to include one or more of the components that this vulnerability affects. These products underwent a thorough evaluation to determine their affectedness by this vulnerability. Note that layered products (such as container-based offerings) that consume affected components from any of the products listed in this table may be affected and are not represented.

Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?

 In order to maintain code stability and compatibility, Red Hat usually does not rebase packages to entirely new versions. Instead, we backport fixes and new features to an older version of the package we distribute. This can result in some security scanners that only consider the package version to report the package as vulnerable. To avoid this, we suggest that you use an approved vulnerability scanner from our This content is not included.Red Hat Vulnerability Scanner Certification program.

My product is listed as "Out of Support Scope". What does this mean?

 When a product is listed as "Out of Support Scope", it means a vulnerability with the impact level assigned to this CVE is no longer covered by its current support lifecycle phase. The product has been identified to contain the impacted component, but analysis to determine whether it is affected or not by this vulnerability was not performed. The product should be assumed to be affected. Customers are advised to apply any mitigation options documented on this page, consider removing or disabling the impacted component, or upgrade to a supported version of the product that has an update available.