CVE-2026-81624
Undertow is a flexible performant web server used in JBoss EAP and WildFly. A flaw was found in how Undertow handles WebSocket connections.
CVSS
7.5
High
EPSS
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KEV
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Exploit Today
0
0-100
Published: Aug 31, 2026 · Last modified: Aug 31, 2026 · CWE-770
Not enough EPSS history yet.
Undertow is a flexible performant web server used in JBoss EAP and WildFly. A flaw was found in how Undertow handles WebSocket connections. Specifically, certain configuration limits like message buffer sizes and session timeouts cannot be adjusted and default to being unlimited. This allows a remote attacker to send large amounts of data or maintain connections indefinitely, potentially crashing the server by exhausting its memory or other resources.
CVECVSSEPSSKEVRExploitTitleMod.
CVE-2026-19873——
——0HTML::FormFu versions through 2.08 for Perl allow resource exhaustion via an unbounded repeat count from the query string in Repeatable elements.
When a Repeatable element has counter_name set, its process method reads the repeat count from the named query string parameter, checks only that it is a positive integer, and passes it to repeat, which deep-clones the element's child subtree once per iteration. Nothing caps the value, and no attribute lets an application impose a limit.
The count is read on every request, before the form decides whether it was submitted, so a plain GET reaches the clone loop with no credentials, no session and no request body. Nesting multiplies: a Repeatable inside a Repeatable takes a counter at each level, so an outer and an inner value of 100 build 10,000 clones.
Once the form is submitted, each cloned field's constraints scan the whole element tree in _find_field_value, so cost grows faster than linearly with the count. A single request exhausts memory and CPU.
The latest release on CPAN is 2.07, from 2018. Version 2.08 exists only in the git repository.3hCVE-2026-82722——
——0Allocation of Resources Without Limits or Throttling vulnerability in ash-project ash_admin lets any client that can reach the admin LiveView exhaust the BEAM atom table and crash the entire node.
Two LiveView event handlers interned atoms from unvalidated client input: AshAdmin.PageLive's set_actor built modules from the resource/domain payload with Module.concat/1, and AshAdmin.Components.Resource.Show's calculate converted every submitted form key with String.to_atom/1. Atoms are never garbage collected and the table is capped, so flooding either event with random names mints a new atom per request until the VM aborts, taking down every application on the node. The fix resolves the submitted resource/domain against the known shown resources and maps calculation keys to declared arguments, so no client-supplied string is interned.
This issue affects ash_admin: from 0.1.0 before 1.3.1.10hCVE-2026-81636——
——0Allocation of Resources Without Limits or Throttling vulnerability in ash-project ash_graphql allows an unauthenticated client to bypass the configured GraphQL query-complexity limit and force an unbounded database read.
AshGraphql.Graphql.Resolver.query_complexity/3 multiplies child complexity by the requested page size only when the argument map contains :limit (offset pagination). Relay connections and keyset pagination use first and last, which never match that clause and fall through to the catch-all that returns child_complexity + 1. A nested relay query such as posts(first: 500) { edges { node { comments(first: 500) { ... } } } } therefore scores as trivially cheap while materializing the full fan-out, passing an Absinthe max_complexity cap that rejects the equivalent limit-based query. The fix adds first and last clauses clamped to the action's page size.
This issue affects ash_graphql: from 0.16.23 before 1.11.0.18hCVE-2026-825623.7 LOW24.1%
——7### Summary
When `qs.parse` is called with `comma: true` and `throwOnLimitExceeded: true`, a comma-separated value under a bracket-push key (`a[]=1,2,3,4`) is split into an array without being compared against `arrayLimit`, while the same value under a flat key (`a=1,2,3,4`), an indexed key (`a[0]=`), a nested key (`a[b]=`), or a dotted key (`a.b=` with `allowDots`) throws the documented `RangeError`. A single parameter such as `a[]=1,2,2,...` therefore produces an inner array of arbitrary length even though the caller opted into the hard limit. This is the `[]=` key form that the fix for CVE-2026-2391 (qs 6.14.2) did not cover.
### Details
In `lib/parse.js`, a comma-separated value under a `[]=` key is split and then wrapped as a single nested element (`val = [val]`, so that each `a[]=x,y` group counts as one element of the outer array). The `arrayLimit` check that 6.14.2 added for comma values runs after that wrap, so for `[]=` parts it only ever saw the wrapper of length 1. 6.15.3 added a pre-split comma count so that an oversized value throws before it is allocated, but gated it on an `isFlatArrayValue` flag that `parseValues` set to `false` for any part containing `[]=`, and did not pass it for object-valued input, so the gap remained.
#### PoC
```js
var qs = require('qs');
var options = { comma: true, arrayLimit: 3, throwOnLimitExceeded: true };
qs.parse('a=1,2,3,4', options); // RangeError: Array limit exceeded. Only 3 elements allowed in an array.
qs.parse('a[]=1,2,3,4', options); // { a: [ [ '1', '2', '3', '4' ] ] } (no throw)
qs.parse('a[]=' + '1,'.repeat(1000000) + '1', { comma: true, arrayLimit: 20, throwOnLimitExceeded: true });
// no throw; a 1,000,001-element inner array is allocated
```
#### Fix
`lib/parse.js`, applied in 8859c37 on `main` and released as v6.16.0: the `isFlatArrayValue` gate is removed, so every comma-split value is counted against `arrayLimit` before splitting regardless of key form. An in-limit group under `a[]=` still counts as one element of the outer array, and the default (`throwOnLimitExceeded: false`) path is unchanged.
### Affected versions
`>=6.14.2 <6.16.0`, fixed in v6.16.0.
v6.14.2 introduced `arrayLimit` enforcement for comma values (the fix for CVE-2026-2391) but only for values not under a `[]=` key, and every release from v6.14.2 through v6.15.3 has the same gap. v6.14.0 and v6.14.1, where `throwOnLimitExceeded` exists but does not apply to any comma form, are covered by CVE-2026-2391 rather than this record. Earlier lines (6.7.x through 6.13.x) have `comma` but no `throwOnLimitExceeded`, so there is no hard cap on any comma path to bypass; releases before 6.7.0 have no `comma` option.
### Impact
An unauthenticated attacker who can reach an application that parses untrusted query strings or urlencoded bodies with both `comma: true` and `throwOnLimitExceeded: true` (both non-default) can bypass the configured limit with a single `a[]=` parameter and force the parser to allocate an array proportional to the request size. The cost is strictly linear in the attacker-supplied bytes (about 0.1 microseconds and 6 to 7 retained bytes per input byte; the same out-of-memory threshold as the documented default `throwOnLimitExceeded: false` path), so a transport-layer request or body size limit bounds it completely (and node's default maximum HTTP header size of 16 KB already bounds the request line, so multi-megabyte payloads need a body parser). The impact is that an opt-in hard limit fails open on one key spelling, not unbounded allocation from a small input.1dCVE-2026-36866.2 MED2.1%
——1IBM Cloud Pak for Data System 11.3.0.2 through Interim Fix 001 is vulnerable to a denial of service due to improper limitation of resources.3dCVE-2026-547887.5 HIG44.4%
——13dd-trace-rs provides Datadog application performance monitoring for Rust. From 0.1.0 until 0.3.3, datadog-opentelemetry/src/propagation/tracecontext.rs parses the W3C tracestate header and collects every semicolon-separated key and value pair in the Datadog dd=... vendor entry into a HashMap without enforcing a pair count or entry size limit. Because tracecontext extraction is enabled by default, a remote unauthenticated attacker can send an arbitrarily large dd=... entry and force excessive CPU and memory consumption for each request, causing denial of service in an instrumented network service. This vulnerability is fixed in 0.3.3.3d