Siemens: >> Simatic Cn 4100 Firmware >> 2.7 Security Vulnerabilities
A vulnerability has been identified in SIMATIC CN 4100 (All versions < V5.0). The affected application is susceptible to resource exhaustion when subjected to high volume of TCP SYN packets
This could allow an attacker to render the service unavailable and cause denial-of-service conditions by overwhelming system resources.
CVSS Score
8.7
EPSS Score
0.003
Published
2026-05-12
A vulnerability has been identified in SIMATIC CN 4100 (All versions < V5.0). The affected application does not properly restrict unauthenticated connections and is susceptible to resource exhaustion conditions.
This could allow an attacker to disrupt normal operations or perform unauthorized actions, potentially impacting system availability and integrity.
CVSS Score
8.8
EPSS Score
0.003
Published
2026-05-12
CVE-2026-31431
In the Linux kernel, the following vulnerability has been resolved:
crypto: algif_aead - Revert to operating out-of-place
This mostly reverts commit 72548b093ee3 except for the copying of
the associated data.
There is no benefit in operating in-place in algif_aead since the
source and destination come from different mappings. Get rid of
all the complexity added for in-place operation and just copy the
AD directly.
Known exploited
CVSS Score
7.8
EPSS Score
0.999
Published
2026-04-22
Issue summary: An OpenSSL TLS 1.3 server may fail to negotiate the expected
preferred key exchange group when its key exchange group configuration includes
the default by using the 'DEFAULT' keyword.
Impact summary: A less preferred key exchange may be used even when a more
preferred group is supported by both client and server, if the group
was not included among the client's initial predicated keyshares.
This will sometimes be the case with the new hybrid post-quantum groups,
if the client chooses to defer their use until specifically requested by
the server.
If an OpenSSL TLS 1.3 server's configuration uses the 'DEFAULT' keyword to
interpolate the built-in default group list into its own configuration, perhaps
adding or removing specific elements, then an implementation defect causes the
'DEFAULT' list to lose its 'tuple' structure, and all server-supported groups
were treated as a single sufficiently secure 'tuple', with the server not
sending a Hello Retry Request (HRR) even when a group in a more preferred tuple
was mutually supported.
As a result, the client and server might fail to negotiate a mutually supported
post-quantum key agreement group, such as 'X25519MLKEM768', if the client's
configuration results in only 'classical' groups (such as 'X25519' being the
only ones in the client's initial keyshare prediction).
OpenSSL 3.5 and later support a new syntax for selecting the most preferred TLS
1.3 key agreement group on TLS servers. The old syntax had a single 'flat'
list of groups, and treated all the supported groups as sufficiently secure.
If any of the keyshares predicted by the client were supported by the server
the most preferred among these was selected, even if other groups supported by
the client, but not included in the list of predicted keyshares would have been
more preferred, if included.
The new syntax partitions the groups into distinct 'tuples' of roughly
equivalent security. Within each tuple the most preferred group included among
the client's predicted keyshares is chosen, but if the client supports a group
from a more preferred tuple, but did not predict any corresponding keyshares,
the server will ask the client to retry the ClientHello (by issuing a Hello
Retry Request or HRR) with the most preferred mutually supported group.
The above works as expected when the server's configuration uses the built-in
default group list, or explicitly defines its own list by directly defining the
various desired groups and group 'tuples'.
No OpenSSL FIPS modules are affected by this issue, the code in question lies
outside the FIPS boundary.
OpenSSL 3.6 and 3.5 are vulnerable to this issue.
OpenSSL 3.6 users should upgrade to OpenSSL 3.6.2 once it is released.
OpenSSL 3.5 users should upgrade to OpenSSL 3.5.6 once it is released.
OpenSSL 3.4, 3.3, 3.0, 1.0.2 and 1.1.1 are not affected by this issue.
CVSS Score
6.5
EPSS Score
0.004
Published
2026-03-13
A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1). The affected application do not properly validate input parameters in its REST API, resulting in improper handling of unexpected arguments.
This could allow an authenticated attacker to execute arbitrary code with limited privileges.
CVSS Score
8.7
EPSS Score
0.006
Published
2025-12-09
A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1). The affected device stores sensitive information in the firmware. This could allow an attacker to access and misuse this information, potentially impacting the device’s confidentiality, integrity, and availability.
CVSS Score
9.2
EPSS Score
0.004
Published
2025-12-09
A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1). The affected device contains a USB port which allows unauthenticated connections. This could allow an attacker with physical access to the device to trigger reboot that could cause denial of service condition.
CVSS Score
5.1
EPSS Score
0.002
Published
2025-12-09
A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1). The affected application exhibits inconsistent SNMP behavior, such as unexpected service availability and unreliable configuration handling across protocol versions. This could allow an attacker to access sensitive data, potentially leading to a breach of confidentiality.
CVSS Score
6.9
EPSS Score
0.004
Published
2025-12-09
A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1). The affected devices exposes server information in its responses.
This could allow an attacker with network access to gain useful information, increasing the likelihood of targeted attacks.
CVSS Score
5.3
EPSS Score
0.003
Published
2025-12-09
CVE-2025-39682
In the Linux kernel, the following vulnerability has been resolved:
tls: fix handling of zero-length records on the rx_list
Each recvmsg() call must process either
- only contiguous DATA records (any number of them)
- one non-DATA record
If the next record has different type than what has already been
processed we break out of the main processing loop. If the record
has already been decrypted (which may be the case for TLS 1.3 where
we don't know type until decryption) we queue the pending record
to the rx_list. Next recvmsg() will pick it up from there.
Queuing the skb to rx_list after zero-copy decrypt is not possible,
since in that case we decrypted directly to the user space buffer,
and we don't have an skb to queue (darg.skb points to the ciphertext
skb for access to metadata like length).
Only data records are allowed zero-copy, and we break the processing
loop after each non-data record. So we should never zero-copy and
then find out that the record type has changed. The corner case
we missed is when the initial record comes from rx_list, and it's
zero length.
Known exploited
CVSS Score
9.8
EPSS Score
0.012
Published
2025-09-05
Page 1