Openssl: >> Openssl Security Vulnerabilities
Issue summary: Receiving a QUIC initial packet with an invalid token may
trigger a NULL pointer dereference in the OpenSSL QUIC server with
address validation disabled.
Impact summary: NULL pointer dereference typically causes abnormal termination
of the affected QUIC server process and a Denial of Service.
If the address validation is disabled in the OpenSSL QUIC server
implementation, an attacker can crash the server by sending an initial
packet with an invalid or expired token.
By default, the client address validation is enabled in the OpenSSL QUIC server
implementation, which makes the default configuration not vulnerable
to this issue. However if the SSL_LISTENER_FLAG_NO_VALIDATE is used with
the SSL_new_listener() call, the address validation is disabled making the
vulnerable code reachable.
The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this
issue, as the affected code is outside the OpenSSL FIPS module boundary.
CVSS Score
7.5
EPSS Score
0.007
Published
2026-06-09
Issue summary: When a partial-chain certificate verification is enabled
together with OCSP response checking for the whole chain, a NULL dereference
will happen if the verified chain does not have a self-signed trusted anchor,
crashing the process.
Impact summary: A NULL pointer dereference can trigger a crash which leads to a
Denial of Service for an application.
When performing OCSP response checking for certificates in the verification
chain, the code always tries to access the next certificate as the issuer.
There is a check for a self-signed certificate. However with the partial
chain verification enabled when the chain does not have a self-signed trusted
anchor, the issuer will be NULL for the last certificate in the chain. A NULL
pointer dereference then happens.
This issue affects only applications which enable both OCSP verification
of the certificate chain (X509_V_FLAG_OCSP_RESP_CHECK_ALL) and partial
chain verification (X509_V_FLAG_PARTIAL_CHAIN) in the certificate
verification. Both flags are disabled by default. For that reason, we have
assigned Low severity to the issue.
No FIPS modules are affected by this issue as the affected code is outside
the OpenSSL FIPS module boundary.
CVSS Score
7.5
EPSS Score
0.004
Published
2026-06-09
Issue summary: A specially crafted password-encrypted CMS message
can trigger a NULL pointer dereference during CMS decryption.
Impact summary: This NULL pointer dereference leads to an application crash
and a Denial of Service.
The CMS PasswordRecipientInfo.keyDerivationAlgorithm field is defined as
OPTIONAL in the ASN.1 specification and may therefore be absent in specially
crafted inputs. During the password-based CMS decryption the OpenSSL
CMS implementation dereferences this field without first checking whether it
was present.
An attacker who supplies such a CMS message to an application performing
password-based CMS decryption can trigger an application crash, leading to
a Denial of Service.
Applications that process password-encrypted CMS messages may be affected.
The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this
issue, as the affected code is outside the OpenSSL FIPS module boundary.
CVSS Score
5.9
EPSS Score
0.006
Published
2026-06-09
Issue summary: Remote peer may exhaust heap memory of the QUIC
server or client by flooding it with packets containing PATH_CHALLENGE
frames.
Impact summary: A malicious remote peer can cause an unbounded
memory allocation which can lead to an abnormal termination of the
application acting as a QUIC client or server and a Denial of Service.
A remote peer may exhaust heap memory by flooding the local
QUIC stack with PATH_CHALLENGE frames. The local QUIC stack
allocates a PATH_RESPONSE frame for every PATH_CHALLENGE it receives.
The allocated PATH_RESPONSE frame gets freed only when the remote
peer acknowledges reception of the PATH_RESPONSE frame which will
not be done by a malicious peer.
The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by
this issue. The QUIC stack is outside of OpenSSL FIPS module
boundary.
CVSS Score
7.5
EPSS Score
0.005
Published
2026-06-09
Issue summary: A malicious server can exploit TLS OCSP stapling by delivering
a crafted response through the status_request extension, triggering a
double-free in the client's certificate verification path.
Impact summary: Successful exploitation allows an attacker to corrupt heap
memory via a double-free, potentially leading to a Denial of Service or
possibly an attacker controlled code execution or other undefined behavior.
If OCSP stapling is enabled and the TLS client connects to a malicious server,
a crafted OCSP stapled response can trigger a double free in the TLS client
when the stapled response is checked.
The OCSP stapling is not enabled by default. Reliable code execution
through a double-free is technically complex and highly environment-dependent
but the Denial of Service impact is straightforward to achieve, warranting
Moderate severity.
No FIPS modules are affected by this issue as the affected code is outside
the OpenSSL FIPS module boundary.
CVSS Score
5.0
EPSS Score
0.002
Published
2026-06-09
Issue summary: Parsing a crafted DER-encoded ASN.1 structure with a primitive
element whose content exceeds 2 gigabytes in length may cause a heap buffer
over-read on 64-bit Unix and Unix-like platforms.
Impact summary: The heap buffer over-read may crash the application (Denial of
Service) or to load into the decoded ASN.1 object contents of memory beyond the
end of the input buffer. More typically such ASN.1 elements would instead be
truncated.
An integer truncation in OpenSSL's ASN.1 decoder causes the content length of
an ASN.1 primitive element to be mishandled when it exceeds 2 gigabytes. In the
worst case the truncated length is treated as a request to scan the binary
content for a terminating zero byte, possibly causing OpenSSL to read either
less than or beyond the end of the allocated buffer.
Applications that pass attacker-supplied data to d2i_X509(), d2i_PKCS7(), or
any other d2i_* decoding function are affected. OpenSSL's own command-line
tools are not vulnerable, as data read through the BIO layer is checked before
it reaches the affected code. The issue only affects 64-bit Unix and Unix-like
platforms; 32-bit platforms and 64-bit Windows are not affected.
The FIPS modules in 4.0, 3.6, 3.5, 3.4 and 3.0 are not affected by this issue,
as the affected code is outside the OpenSSL FIPS module boundary.
CVSS Score
7.5
EPSS Score
0.005
Published
2026-06-09
Issue Summary: The PKCS#12 file processing fails to perform sufficient input
validation for files that use Password-Based Message Authentication Code 1
(PBMAC1) integrity mechanism allowing a certificate and private key forgery.
Impact Summary: An attacker impersonating a user can cause a service reading
PKCS#12 files to accept forged certificates and private keys with a 1 in 256
probability.
If a service accepting PKCS#12 files is using passwords for authenticating
the received files, the attacker can create unencrypted PKCS#12 files that
use PBMAC1 authentication that specifies an HMAC key of only one byte, allowing
them to craft a file that will be accepted with a 1 in 256 probability.
That would then cause the service to accept a certificate and private key
controlled by the attacker.
The FIPS modules are not affected by this issue, as the affected code is
outside the OpenSSL FIPS module boundary.
CVSS Score
7.4
EPSS Score
0.002
Published
2026-06-09
Issue Summary: Cryptographic Message Services (CMS) processing fails to perform
sufficient input validation on the cipher and tag length fields of
AuthEnvelopedData containers, leading to various potential compromises.
Impact Summary: Attackers making use of these vulnerabilities may achieve
key-equivalent functionality for a given CMS recipient and/or bypass integrity
validation for a given message.
In one use case, an attacker may send a CMS message containing
AuthEnvelopedData with the cipher specified as a non-AEAD cipher. OpenSSL
erroneously allows this selection, and attempts to decrypt and validate the
message.
An on-path attacker who captures one legitimate AES-GCM AuthEnvelopedData
addressed to the victim can re-emit it with the recipientInfos set left
byte-for-byte intact, so the victim's private key still unwraps the genuine CEK
(the content-encryption key), but with the inner OID rewritten to AES-256-OFB
(Output Feedback Mode, an unauthenticated keystream mode) and with an
attacker-chosen IV and ciphertext. The victim initializes AES-256-OFB under the
real CEK, never consults the MAC field, and CMS_decrypt() returns success.
If the application under attack responds to the attacker with any indicator
showing success or failure of the decryption effort, it is possible for the
attacker to use this as an oracle to obtain key equivalent functionality for the
CEK used for the chosen recipient of the message.
In another use case, an attacker can reduce the tag length of the chosen AEAD
cipher for a given AuthEnvelopedData container to be a single byte long,
allowing an attacker to brute force CMS decryption, producing an integrity
bypass for applications that trust CMS_decrypt() to reject modified content.
The FIPS modules are not affected by this issue.
CVSS Score
9.1
EPSS Score
0.002
Published
2026-06-09
Issue summary: During processing of a crafted CMS EnvelopedData message
with KeyAgreeRecipientInfo a NULL pointer dereference can happen.
Impact summary: Applications that process attacker-controlled CMS data may
crash before authentication or cryptographic operations occur resulting in
Denial of Service.
When a CMS EnvelopedData message that uses KeyAgreeRecipientInfo is
processed, the optional parameters field of KeyEncryptionAlgorithmIdentifier
is examined without checking for its presence. This results in a NULL
pointer dereference if the field is missing.
Applications and services that call CMS_decrypt() on untrusted input
(e.g., S/MIME processing or CMS-based protocols) are vulnerable.
The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this
issue, as the affected code is outside the OpenSSL FIPS module boundary.
CVSS Score
7.5
EPSS Score
0.008
Published
2026-04-07
Issue summary: During processing of a crafted CMS EnvelopedData message
with KeyTransportRecipientInfo a NULL pointer dereference can happen.
Impact summary: Applications that process attacker-controlled CMS data may
crash before authentication or cryptographic operations occur resulting in
Denial of Service.
When a CMS EnvelopedData message that uses KeyTransportRecipientInfo with
RSA-OAEP encryption is processed, the optional parameters field of
RSA-OAEP SourceFunc algorithm identifier is examined without checking
for its presence. This results in a NULL pointer dereference if the field
is missing.
Applications and services that call CMS_decrypt() on untrusted input
(e.g., S/MIME processing or CMS-based protocols) are vulnerable.
The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this
issue, as the affected code is outside the OpenSSL FIPS module boundary.
CVSS Score
7.5
EPSS Score
0.008
Published
2026-04-07