SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-22901

curl 7.75.0 through 7.76.1 suffers from a use-after-free vulnerability resulting in already freed memory being used when a TLS 1.3 session ticket arrives over a connection.

HIGH 8.1EPSS 60.1%

Does this matter?

EPSS puts the probability of exploitation in the next 30 days at 60.1%, higher than 99% of all known CVEs. Patch or mitigate before the next change window.

Description

curl 7.75.0 through 7.76.1 suffers from a use-after-free vulnerability resulting in already freed memory being used when a TLS 1.3 session ticket arrives over a connection. A malicious server can use this in rare unfortunate circumstances to potentially reach remote code execution in the client. When libcurl at run-time sets up support for TLS 1.3 session tickets on a connection using OpenSSL, it stores pointers to the transfer in-memory object for later retrieval when a session ticket arrives. If the connection is used by multiple transfers (like with a reused HTTP/1.1 connection or multiplexed HTTP/2 connection) that first transfer object might be freed before the new session is established on that connection and then the function will access a memory buffer that might be freed. When using that memory, libcurl might even call a function pointer in the object, making it possible for a remote code execution if the server could somehow manage to get crafted memory content into the correct place in memory.

CVSS 3.1
8.1 HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
60.12% probability · 99th percentile
CISA KEV
Not listed
Weakness
CWE-416
Affected
haxx/curl · oracle/communications cloud native core binding support function · oracle/communications cloud native core network function cloud native environment · oracle/communications cloud native core network repository function · oracle/communications cloud native core network slice selection function · oracle/communications cloud native core service communication proxy · oracle/essbase · oracle/mysql server · netapp/active iq unified manager · netapp/cloud backup · netapp/oncommand insight · netapp/oncommand workflow automation · netapp/snapcenter · netapp/solidfire\, enterprise sds \& hci storage node · netapp/solidfire \& hci management node · netapp/solidfire baseboard management controller firmware · netapp/hci compute node firmware · netapp/h300e firmware · netapp/h300s firmware · netapp/h410s firmware · +6 more
Source
support@hackerone.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.