| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| 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 |
| An authenticated user is able to cause disproportionate CPU load on the Frontend webserver by sending specifically crafted requests to the Frontend validate.api.exists action, leading to potential denial of service. |
| An unauthenticated user is able to cause disproportionate CPU load on the Frontend webserver by sending specifically crafted requests to the Frontend popup.testtriggerexpr action, leading to potential denial of service. |
| Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.4.21, 4.5.14, 4.6.4, and 4.7.0-beta.1, the administrative statistics endpoints handled by Api::V1::Admin::MeasuresController and Api::V1::Admin::RetentionController checked authorization only after beginning expensive calculations. Anonymous callers could submit keys, start_at, and end_at parameters that caused long-running SQL queries in Admin::Metrics::Measure, Admin::Metrics::Retention, and Admin::Metrics::Dimension::BaseDimension, allowing repeated requests to exhaust server resources. This issue is fixed in versions 4.4.21, 4.5.14, 4.6.4, and 4.7.0-beta.1. |
| AutoGPT is a workflow automation platform for creating, deploying, and managing continuous artificial intelligence agents. Prior to 0.6.32, there is a DoS vulnerability in AITextSummarizerBlock. Malicious users can amplify their input. For example, if a malicious user inputs 10K of content, the server will consume 50G of memory, eventually causing memory resources to be exhausted, resulting in DoS. This vulnerability is fixed in 0.6.32. |
| UBB.threads is vulnerable to Denial of Service (DoS). By sending multiple concurrent requests to view any user profile on instances with many registered users, an authenticated attacker can easily exhaust database resources and completely deny access to the application for other users.
Because vendor contact attempts were unsuccessful, the vulnerability has only been confirmed in version 7.7.5 but may also affect other versions. |
| Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to versions 1.35.11, 1.36.7, 1.37.3, and 1.38.1, a vulnerability in Envoy's HTTP/2 downstream request processing allows an unauthenticated remote client to trigger excessive memory consumption, potentially resulting in OOM termination of the Envoy process and denial of service. The issue arises from the combination of two behaviors. First, cookie header bytes are not fully accounted for during request header size validation in Envoy. Second, HPACK header block limits in oghttp2/quiche are enforced on encoded bytes without a corresponding limit on total decoded header size. Together, these behaviors allow a malicious client to cause large decoded header allocations while bypassing the intended request header size protections. Versions 1.35.11, 1.36.7, 1.37.3, and 1.38.1 contain a fix. No complete workaround is known short of applying a fix. Possible temporary mitigations include disabling downstream HTTP/2 where operationally feasible; enforcing stricter request header and cookie limits before traffic reaches Envoy; and monitoring Envoy memory usage for abnormal growth under HTTP/2 traffic. |
| Text::LineFold versions through 2019.001 for Perl duplicate the output based on the number of special break characters.
Text::LineFold splits the input string by specific line break characters (such as VT, FF and others) into segments, but applies the break function to the entire string, not just the segment.
A side effect of this is that the full input can be duplicated for each segment. Besides being incorrect, this can lead to unexpected resource consumption and possible denial of service.
Note that Text::LineFold is part of the Unicode-LineBreak distribution, which may have a higher version number than the module. |
| Technitium DNS Server aggressively tries to fetch missing RRSIG records or mismatched DNSKEY records. An attacker in control of a domain can cause a vulnerable system to generate excessive network traffic. Fixed in 15.0. |
| Deskflow is a keyboard and mouse sharing app. Prior to 1.26.0.167, a remote, unauthenticated denial of service (DoS) vulnerability affects Deskflow servers running with TLS enabled (the default). When any TCP peer connects to the listening port and its first bytes do not parse as a valid TLS ClientHello, SecureSocket::secureAccept enters its fatal-error branch and calls Arch::sleep(1) (a blocking 1-second sleep) on the multiplexer worker thread. That thread services every socket on the server, including established TLS clients delivering mouse motion, keyboard events, and clipboard updates. A single failed handshake therefore stalls input delivery to all connected screens for ~1 second, and a sustained drip of malformed connections (≥ 1/s) makes the server effectively unusable while the attack persists. This vulnerability is fixed in 1.26.0.167. |
| Svelte devalue is a JavaScript library that serializes values into strings when JSON.stringify isn't sufficient for the job. From 5.1.0 to 5.6.1, certain inputs can cause devalue.parse to consume excessive CPU time and/or memory, potentially leading to denial of service in systems that parse input from untrusted sources. This affects applications using devalue.parse on externally-supplied data. The root cause is the ArrayBuffer hydration expecting base64 encoded strings as input, but not checking the assumption before decoding the input. This vulnerability is fixed in 5.6.2. |
| A series of specifically crafted, unauthenticated messages can exhaust available memory and crash a MongoDB server. |
| Svelte devalue is a JavaScript library that serializes values into strings when JSON.stringify isn't sufficient for the job. From 5.3.0 to 5.6.1, certain inputs can cause devalue.parse to consume excessive CPU time and/or memory, potentially leading to denial of service in systems that parse input from untrusted sources. This affects applications using devalue.parse on externally-supplied data. The root cause is the typed array hydration expecting an ArrayBuffer as input, but not checking the assumption before creating the typed array. This vulnerability is fixed in 5.6.2. |
| SAP BusinessObjects BI Platform allows an unauthenticated attacker to send specially crafted requests that could cause the Content Management Server (CMS) to crash and automatically restart. By repeatedly submitting these requests, the attacker could induce a persistent service disruption, rendering the CMS completely unavailable. Successful exploitation results in a high impact on availability, while confidentiality and integrity remain unaffected. |
| SAP BusinessObjects Business Intelligence Platform (AdminTools) allows an authenticated attacker with user privileges to execute a specific query in AdminTools that could cause the Content Management Server (CMS) to crash, rendering the CMS partially or completely unavailable and resulting in the denial of service of the Content Management Server (CMS). Successful exploitation impacts system availability, while confidentiality and integrity remain unaffected. |
| OpenClaw before 2026.3.22 contains an unauthenticated resource exhaustion vulnerability in voice call webhook handling that buffers request bodies before provider signature checks. Attackers can send large or malicious webhook requests to exhaust server resources without authentication by bypassing signature validation. |
| SAP NetWeaver remote service for Xcelsius allows an attacker with network access and high privileges to execute arbitrary code on the affected system due to insufficient input validation and improper handling of remote method calls. Exploitation does not require user interaction and could lead to service disruption or unauthorized system control. This has high impact on integrity and availability, with no impact on confidentiality. |
| Botan is a C++ cryptography library. X.509 certificates can identify elliptic curves using either an object identifier or using explicit encoding of the parameters. Prior to 3.5.0 and 2.19.5, checking name constraints in X.509 certificates is quadratic in the number of names and name constraints. An attacker who presented a certificate chain which contained a very large number of names in the SubjectAlternativeName, signed by a CA certificate which contained a large number of name constraints, could cause a denial of service. The problem has been addressed in Botan 3.5.0 and a partial backport has also been applied and is included in Botan 2.19.5. |
| Botan is a C++ cryptography library. X.509 certificates can identify elliptic curves using either an object identifier or using explicit encoding of the parameters. Prior to versions 3.3.0 and 2.19.4, an attacker could present an ECDSA X.509 certificate using explicit encoding where the parameters are very large. The proof of concept used a 16Kbit prime for this purpose. When parsing, the parameter is checked to be prime, causing excessive computation. This was patched in 2.19.4 and 3.3.0 to allow the prime parameter of the elliptic curve to be at most 521 bits. No known workarounds are available. Note that support for explicit encoding of elliptic curve parameters is deprecated in Botan. |
| It is possible to construct a zone such that some queries to it will generate responses containing numerous records in the Additional section. An attacker sending many such queries can cause either the authoritative server itself or an independent resolver to use disproportionate resources processing the queries. Zones will usually need to have been deliberately crafted to attack this exposure.
This issue affects BIND 9 versions 9.11.0 through 9.11.37, 9.16.0 through 9.16.50, 9.18.0 through 9.18.32, 9.20.0 through 9.20.4, 9.21.0 through 9.21.3, 9.11.3-S1 through 9.11.37-S1, 9.16.8-S1 through 9.16.50-S1, and 9.18.11-S1 through 9.18.32-S1. |
