Issue summary: Receiving a DTLS record for a future epoch while a handshake
is in progress causes OpenSSL to buffer far more memory than the record
itself requires.
Impact summary: A peer can use a small amount of network traffic to make an
OpenSSL DTLS endpoint retain a disproportionately large amount of memory,
which may lead to a Denial of Service.
CWE: CWE-405: Asymmetric Resource Consumption (Amplification)
Description: While a DTLS handshake is in progress, a peer may legitimately
have already moved on to the next epoch (for example, having sent its
ChangeCipherSpec and Finished messages) before the local endpoint has
processed the same transition, typically because of reordering on the
underlying UDP transport. OpenSSL buffers such early records so that they
can be processed once the local endpoint catches up.
Buffering a record currently retains the entire read buffer it arrived in,
which is sized to hold the largest possible DTLS record (around 16
kilobytes), rather than just the bytes that make up the record itself. Up
to 100 such records may be buffered per connection. As a result, a peer
that sends a stream of small forged records claiming to belong to the next
epoch can cause an OpenSSL DTLS endpoint to retain around 1.7 megabytes of
memory, despite sending only a small fraction of that amount of data over
the network.
An attacker therefore gains a memory amplification factor of around 1200,
and can multiply the effect across as many associations as it is able to
open, making this a remote memory exhaustion Denial of Service risk for
DTLS servers. Since the memory retained per connection remains bounded,
and any limit an application already places on the number of concurrent
associations also bounds the total exposure, this issue has been assessed
as Low severity.
FIPS impact: no
No FIPS modules are affected by this issue as the affected code is outside
the OpenSSL FIPS module boundary.
OpenSSL 4.0, 3.6, 3.5, 3.4, 3.0, 1.1.1 and 1.0.2 are vulnerable to this
issue.
OpenSSL 4.0 users should upgrade to OpenSSL 4.0.2.
OpenSSL 3.6 users should upgrade to OpenSSL 3.6.4.
OpenSSL 3.5 users should upgrade to OpenSSL 3.5.8.
OpenSSL 3.4 users should upgrade to OpenSSL 3.4.7.
OpenSSL 3.0 users should upgrade to OpenSSL 3.0.22.
Premium support customers only:
OpenSSL 1.1.1 users should upgrade to OpenSSL 1.1.1zi
OpenSSL 1.0.2 users should upgrade to OpenSSL 1.0.2zr
This issue was reported on 18 May 2026 by Amazon Web Services.
The fix has been developed by Matt Caswell.
-- cut (non-publishing metadata for internal use) --
Reported by: Amazon Web Services
Fixed by: Matt Caswell
Issue summary: In a server or client configuration with RFC7250 Raw Public Keys (RPKs)
enabled, and only the private key (with no associated certificate) configured locally,
a NULL pointer dereference may occur when the remote peer solicits raw public keys and
also sends the typically omitted "signature_algorithms_cert" TLS extension.
Impact summary: The impact is limited to a possible Denial of Service as a result of
an application abort, no data disclosure or remote command execution are possible.
CWE: CWE-476: NULL Pointer Dereference
Description: While a passing comment in sample code in the documentation suggests
that key-only RPK configurations are supported, the best-practice RPK configuration
is to always configure a corresponding certificate (possibly self-signed or
signed by any convenient CA).
When the private key is configured along with a matching certificate, the
"signature_algorithms_cert" extension is handled reliably even without the
fix, and peer clients or servers that don't support raw public keys may be
able to complete a TLS connection by pinning or verifying the corresponding
certificate or its public key.
Deployments that prefer to configure just a private key with no certificate
need to upgrade to an updated release as noted below.
FIPS impact: no
No FIPS modules are affected by this issue, as the SSL protocol implementation
is outside the OpenSSL FIPS module boundary.
NLTK versions before 3.10.3 contain a remote code execution vulnerability in allowlisted pickle loaders that trust entire module namespaces instead of specific safe callables. Attackers can craft malicious pickle payloads invoking dangerous in-namespace functions like ReppTokenizer._execute and numpy.f2py.crackfortran.myeval through pickle REDUCE to execute arbitrary commands during model or tokenizer artifact loading.
SQL injection in Hive Metastore direct SQL partition-name resolution in Apache Hive before 4.2.1 on all platforms allows authenticated users with access to Hive Metastore APIs to read, modify, or affect unintended partition metadata (including statistics updates, truncation targets, and file-metadata cache operations) via crafted partition names in metastore RPC requests when direct SQL is enabled (the default). Users are recommended to upgrade to version 4.2.1, which fixes this issue.
Details about the issue:
Several Hive Metastore RPCs resolve partitions by full partition name (PART_NAME) through direct-SQL helpers. In those paths, client-supplied partition names are embedded into SQL using string concatenation (DirectSqlUpdatePart.quoteString() → '...') instead of bind parameters. A partition name containing a single quote (and crafted SQL) can alter the generated WHERE clause so that lookups intended for one partition match additional rows. That can affect reads, stats updates, truncate targets, metadata-cache targets, and related operations when metastore.try.direct.sql is enabled (default: true). An authenticated or network-trusted caller with the ability to invoke Hive Metastore partition-name APIs against a target table (directly or via Hive/other clients), when direct SQL is enabled can perform this attack. Also, the impact is mainly within table & partition targeting (read/update/truncate/drop/cache the wrong partitions in a table they can reference), not arbitrary cross-database access via this bug alone.
An improper authentication vulnerability in HiveServer2 SAML bearer-token validation in Apache Hive 4.0.0 through 4.2.0 (and later unreleased branches) on deployments using HTTP transport with hive.server2.authentication=SAML allows an unauthenticated network attacker to authenticate as an arbitrary Hive user and obtain an authenticated HiveServer2 session via a forged Authorization: Bearer token sent to the /cliservice HTTP endpoint. Users are recommended to upgrade to 4.2.1 version that includes the fix for this issue.
Access / authorization required: No Hive credentials, SAML IdP login, or knowledge of the server signing secret is required. The attacker only needs network reachability to the HiveServer2 HTTP port (typically /cliservice), directly or through a reverse proxy such as Apache Knox that forwards unauthenticated requests to HS2. The instance must have SAML authentication enabled in HTTP mode. Deployments where Knox handles SSO and HiveServer2 uses LDAP/Kerberos (not native SAML mode) are not affected by this specific issue.
Server-Side Request Forgery (SSRF) in Avro SerDe schema resolution in Apache Hive before 4.2.1 allows an authenticated remote attacker with CREATE TABLE privilege to cause the Hive server to fetch an attacker-controlled URL when resolving the avro.schema.url table property on an Avro table that is subsequently queried. This can expose cloud instance metadata, internal network services, or local server files to the Hive process identity. Users are recommended to upgrade to version 4.2.1, which fixes this issue.
Attacker access requirements:
* Network access to HiveServer2 / Metastore: required (remote attacker model).
* Valid Hive authentication: required.
* CREATE TABLE (or equivalent) privilege: required, so the attacker can set avro.schema.url in table properties.
* SELECT privilege on the malicious table: not required for the creator, who can typically query their own table; any other user granted SELECT can also trigger the fetch.
* Write access to the table LOCATION: not required; the attack uses the schema URL, not the data path.
* Admin / superuser privileges: not required; an ordinary authenticated user with DDL rights is sufficient.
* External tables enabled: typically required in practice, and enabled by default in most deployments.
Detection guidance:
* Inspect metastore / Hive table metadata for Avro tables whose avro.schema.url uses unexpected schemes such as http, https, file, or ftp, or points at link-local / cloud metadata addresses (for example 169.254.169.254) or other internal hosts.
* Review HiveServer2 and Metastore logs around CREATE/ALTER TABLE and queries against Avro tables for schema-resolution failures or outbound fetches of avro.schema.url.
* Correlate CREATE TABLE / ALTER TABLE activity that sets avro.schema.url with subsequent SELECT activity on the same table, especially when the URL target is unusual for schema distribution.
* On cloud deployments, check instance / VPC flow logs and metadata service access logs for unexpected requests from Hive host identities shortly after Avro DDL or query activity.
General user can mint admin access tokens via /access-tokens
This issue affects Apache DolphinScheduler: before 3.4.2.
Users are recommended to upgrade to version 3.4.2, which fixes the issue.
hbs is an Express view engine that wraps Handlebars. Its registerAsyncHelper API bypasses Handlebars' automatic HTML escaping: an async helper returns an opaque placeholder during the first render pass, so the double-brace expression escapes only the placeholder, and after rendering hbs substitutes the placeholder with the raw callback return value without escaping it, across the cached, uncached, and layout render paths. An application that passes attacker-influenced data, for example user-supplied content from a database, into an async helper callback can therefore have arbitrary HTML and JavaScript injected into the server-rendered page, resulting in stored or reflected cross-site scripting. Versions 2.1.0 through 4.2.1 are affected, and the issue is fixed in 4.3.0, which HTML-escapes async helper output. Applications that intentionally emit raw HTML from an async helper can opt in explicitly with hbs.SafeString. Users should upgrade to 4.3.0.
NLTK before 3.10.0 (affected versions <=3.9.4) contains an unsafe pickle deserialization vulnerability in the TransitionParser.parse() method (nltk/parse/transitionparser.py). The method calls pickle_load() with the default restricted=False, routing deserialization through WarningUnpickler, which does not override find_class() and therefore permits arbitrary class resolution. When an application loads an attacker-crafted model file, embedded pickle gadget chains execute arbitrary Python code with the privileges of the user running the application. NLTK provides a RestrictedUnpickler for safe deserialization, but it is not used by production code paths. Fixed in 3.10.0.