// For flags

CVE-2024-4741

Use After Free with SSL_free_buffers

Severity Score

7.5
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Attend
*SSVC
Descriptions

Issue summary: Calling the OpenSSL API function SSL_free_buffers may cause
memory to be accessed that was previously freed in some situations

Impact summary: A use after free can have a range of potential consequences such
as the corruption of valid data, crashes or execution of arbitrary code.
However, only applications that directly call the SSL_free_buffers function are
affected by this issue. Applications that do not call this function are not
vulnerable. Our investigations indicate that this function is rarely used by
applications.

The SSL_free_buffers function is used to free the internal OpenSSL buffer used
when processing an incoming record from the network. The call is only expected
to succeed if the buffer is not currently in use. However, two scenarios have
been identified where the buffer is freed even when still in use.

The first scenario occurs where a record header has been received from the
network and processed by OpenSSL, but the full record body has not yet arrived.
In this case calling SSL_free_buffers will succeed even though a record has only
been partially processed and the buffer is still in use.

The second scenario occurs where a full record containing application data has
been received and processed by OpenSSL but the application has only read part of
this data. Again a call to SSL_free_buffers will succeed even though the buffer
is still in use.

While these scenarios could occur accidentally during normal operation a
malicious attacker could attempt to engineer a stituation where this occurs.
We are not aware of this issue being actively exploited.

The FIPS modules in 3.3, 3.2, 3.1 and 3.0 are not affected by this issue.

A use-after-free vulnerability was found in OpenSSL. Calling the OpenSSL API SSL_free_buffers function may cause memory to be accessed that was previously freed in some situations.

*Credits: William Ahern (Akamai), Matt Caswell, Watson Ladd (Akamai)
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
Low
* Common Vulnerability Scoring System
SSVC
  • Decision:Attend
Exploitation
None
Automatable
Yes
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-05-10 CVE Reserved
  • 2024-06-06 CVE Published
  • 2024-11-13 CVE Updated
  • ---------- EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-416: Use After Free
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
OpenSSL
Search vendor "OpenSSL"
OpenSSL
Search vendor "OpenSSL" for product "OpenSSL"
>= 3.3.0 < 3.3.1
Search vendor "OpenSSL" for product "OpenSSL" and version " >= 3.3.0 < 3.3.1"
en
Affected
OpenSSL
Search vendor "OpenSSL"
OpenSSL
Search vendor "OpenSSL" for product "OpenSSL"
>= 3.2.0 < 3.2.2
Search vendor "OpenSSL" for product "OpenSSL" and version " >= 3.2.0 < 3.2.2"
en
Affected
OpenSSL
Search vendor "OpenSSL"
OpenSSL
Search vendor "OpenSSL" for product "OpenSSL"
>= 3.1.0 < 3.1.6
Search vendor "OpenSSL" for product "OpenSSL" and version " >= 3.1.0 < 3.1.6"
en
Affected
OpenSSL
Search vendor "OpenSSL"
OpenSSL
Search vendor "OpenSSL" for product "OpenSSL"
>= 3.0.0 < 3.0.14
Search vendor "OpenSSL" for product "OpenSSL" and version " >= 3.0.0 < 3.0.14"
en
Affected