Bug 2179069 (CVE-2023-27534)

Summary: CVE-2023-27534 curl: SFTP path ~ resolving discrepancy
Product: [Other] Security Response Reporter: Marian Rehak <mrehak>
Component: vulnerabilityAssignee: Nobody <nobody>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: andrew.slice, bodavis, csutherl, dbhole, jclere, kdudka, omajid, peholase, pjindal, plodge, szappis
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Fixed In Version: curl 8.0.0 Doc Type: If docs needed, set a value
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2179106, 2179107, 2179108, 2180434, 2180436    
Bug Blocks: 2178228    

Description Marian Rehak 2023-03-16 14:59:18 UTC 
curl supports SFTP transfers. curl's SFTP implementation offers a special feature in the path component of URLs: a tilde (`~`) character as the first
path element in the path to denotes a path relative to the user's home directory. This is supported because of wording in the [once proposed
to-become RFC draft](https://datatracker.ietf.org/doc/html/draft-ietf-secsh-scp-sftp-ssh-uri-04) that was to dictate how SFTP URLs work. Due to a bug, the handling of the tilde in SFTP path did however not only replace it when it is used stand-alone as the first path element but also wrongly when used as a mere prefix in the first element. Using a path like `/~2/foo` when accessing a server using the user `dan` (with home directory `/home/dan`) would then quite suprisingly access the file `/home/dan2/foo`. This can be taken advantage of to circumvent filtering or worse.
Comment 2 Sandipan Roy 2023-03-21 13:05:05 UTC 
Created curl tracking bugs for this issue:

Affects: fedora-all [bug 2180434]


Created mingw-curl tracking bugs for this issue:

Affects: fedora-all [bug 2180436]
Comment 5 errata-xmlrpc 2023-07-18 17:29:16 UTC 
This issue has been addressed in the following products:

  JBCS httpd 2.4.51.sp2

Via RHSA-2023:3355 https://access.redhat.com/errata/RHSA-2023:3355
Comment 6 errata-xmlrpc 2023-07-18 17:29:40 UTC 
This issue has been addressed in the following products:

  JBoss Core Services on RHEL 7
  JBoss Core Services for RHEL 8

Via RHSA-2023:3354 https://access.redhat.com/errata/RHSA-2023:3354
Comment 7 errata-xmlrpc 2023-11-07 08:22:31 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2023:6679 https://access.redhat.com/errata/RHSA-2023:6679