Bug 2001527 (CVE-2021-22945) - CVE-2021-22945 curl: use-after-free and double-free in MQTT sending
Summary: CVE-2021-22945 curl: use-after-free and double-free in MQTT sending
Alias: CVE-2021-22945
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
Depends On: 2001541 2004362 2004647
Blocks: 2001529
TreeView+ depends on / blocked
Reported: 2021-09-06 10:02 UTC by Dhananjay Arunesh
Modified: 2022-11-23 05:47 UTC (History)
41 users (show)

Fixed In Version: curl-7.79.0
Doc Type: If docs needed, set a value
Doc Text:
A flaw was found in libcurl. When sending data to an MQTT server could in some situations lead to libcurl using already freed memory and then try to free it again. The highest threat from this vulnerability is to data confidentiality as well as system availability.
Clone Of:
Last Closed: 2022-05-17 13:16:53 UTC

Attachments (Terms of Use)

Description Dhananjay Arunesh 2021-09-06 10:02:37 UTC
When sending data to an MQTT server, libcurl could in some circumstances erroneously keep a pointer to an already freed memory area and both use that again in a subsequent call to send data and also free it *again*.

Comment 5 gkamathe 2021-09-15 06:27:18 UTC
Created curl tracking bugs for this issue:

Affects: fedora-all [bug 2004362]

Comment 7 ayambast 2021-09-28 06:47:16 UTC
Marking dotnetv3.1 as NOT affected and closing its tracker as it uses curl v7.61 that isn't affected by this CVE.

Comment 9 Product Security DevOps Team 2022-05-17 13:16:50 UTC
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):


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