Bug 1970902 (CVE-2021-22925)

Summary:	CVE-2021-22925 curl: Incorrect fix for CVE-2021-22898 TELNET stack contents disclosure
Product:	[Other] Security Response	Reporter:	Tomas Hoger <thoger>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	amctagga, andrew.slice, anharris, bniver, bodavis, csutherl, dbhole, drusek, erik-fedora, flucifre, gmeno, gzaronik, hhorak, hvyas, jclere, jorton, jwon, kanderso, kdudka, krathod, luhliari, lvaleeva, mbenjamin, mhackett, mike, msekleta, mturk, omajid, paul, pjindal, rwagner, security-response-team, sostapov, svashisht, szappis, vereddy
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	curl 7.78.0	Doc Type:	If docs needed, set a value
Doc Text:	A flaw was found in the way curl handled telnet protocol option for sending environment variables, which could lead to sending of uninitialized data from a stack-based buffer to the server. This issue leads to potentially revealing sensitive internal information to the server using a clear-text network protocol.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-11-09 23:22:48 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1970934, 1970935, 1970936, 1984328, 1984329
Bug Blocks:	1970904

Description Tomas Hoger 2021-06-11 12:33:06 UTC

CVE-2021-22898: TELNET stack contents disclosure (see bug 1964887) issue was recently reported for curl and it was addressed in curl 7.77.0:

https://curl.se/docs/CVE-2021-22898.html
https://github.com/curl/curl/commit/39ce47f219b09c380b81f89fe54ac586c8db6bde
https://hackerone.com/reports/1176461

However, the fix applied is not correct and does not completely address the issue.  It helps in cases when long environment variable name is used ('a'*256 + ',b'), but not when the name is short and only the value is long ('a,' + 'b'*256, which is the example mentioned in the curl project advisory).

Long variable values still trigger memory disclosure as described in the original report.

This issue was reported upstream via:

https://hackerone.com/reports/1223882

Comment 5 Marian Rehak 2021-07-21 09:15:32 UTC

Created curl tracking bugs for this issue:

Affects: fedora-all [bug 1984328]


Created mingw-curl tracking bugs for this issue:

Affects: fedora-all [bug 1984329]

Comment 8 errata-xmlrpc 2021-11-09 19:02:45 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2021:4511 https://access.redhat.com/errata/RHSA-2021:4511

Comment 9 Product Security DevOps Team 2021-11-09 23:22:43 UTC

This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2021-22925

Comment 10 Tomas Hoger 2022-05-26 11:34:27 UTC

Upstream advisory:
https://curl.se/docs/CVE-2021-22925.html