NLTK before 3.10.4 Denial of Service via SteppingRecursiveDescentParser.parse()

NLTK before 3.10.4 contains an uncontrolled resource consumption vulnerability in SteppingRecursiveDescentParser.parse() that lacks any max_time deadline or step limit. Attackers influencing the grammar can supply an ambiguous self-embedding grammar and short token input to force unbounded top-down search, pinning CPU cores and exhausting worker pools.

Fleet before 4.86.2 Unauthenticated DoS via SSO Callback XML Canonicalization

Fleet before 4.86.2 contains a denial of service vulnerability that allows unauthenticated attackers to exhaust server memory through quadratic XML canonicalization of unsigned SAML responses. Attackers can send a single crafted SAML response with deeply nested elements declaring new namespace prefixes to POST /api/v1/fleet/sso/callback, crashing the Fleet server.

Coder from 2.38.0 before 2.38.4 Memory Exhaustion DoS via Web Push

Coder 2.21.0 before 2.29.24, 2.30.0 before 2.34.16, 2.35.0 before 2.36.11, 2.37.0 before 2.37.8, and 2.38.0 before 2.38.4 reads Web Push endpoint responses in webpushSend with io.ReadAll, without a size limit or client timeout. Any authenticated user can register a subscription via POST /api/v2/users/{user}/webpush/subscription pointing to a server returning an endless body, exhausting coderd memory and crashing the API, dashboard, and workspace connections.

OpenEMR before 8.5.0 Denial of Service via ZIP Upload Decompression

OpenEMR before 8.5.0 contains a denial of service vulnerability in four ZIP upload paths that read uncompressed entries into memory without size or ratio checks. Authenticated billing or Carecoordination users can upload highly compressed ZIP archives to exhaust PHP memory and worker pools, making OpenEMR unavailable.

FrankenPHP before 1.13.4 Pending Worker Request Denial of Service

FrankenPHP before 1.13.4 contains a denial of service vulnerability in worker mode where frankenphp_handle_request() returns false without finishing the dequeued request after a fatal error during request startup. Attackers who trigger startup fatal errors against worker scripts that keep calling frankenphp_handle_request() can leave client requests hanging indefinitely while the worker continues running.

FrankenPHP before 1.13.2 Denial of Service via Queued Disconnected Requests

FrankenPHP before 1.13.2 contains a resource exhaustion vulnerability that allows unauthenticated clients to tie up PHP threads because queued requests are not cancelled when clients disconnect. Attackers can send many requests and close connections immediately, forcing handleRequestWithRegularPHPThreads and worker handlers to execute them and delay all clients sharing the thread pool.

Scapy before 2.8.0 Denial of Service via Quadratic BER OID Decoding

Scapy before 2.8.0 contains a denial of service vulnerability in BER_num_dec() and BERcodec_OID.do_dec() that allows remote attackers to exhaust CPU by supplying oversized OID arcs. Attackers can send ASN.1/BER data with many base-128 continuation bytes to cause quadratic CPU consumption or an uncaught ValueError crash on Python 3.11+.

actix-http before 3.20.1 and actix-web before 4.18.2 Decompression Bomb DoS via encoding::Decoder

actix-http before 3.20.1 and actix-web before 4.18.2 contain an unbounded decompression vulnerability in encoding::Decoder that lets remote attackers exhaust memory and CPU via compressed bodies. Attackers can send small highly compressed gzip, deflate, Brotli or zstd request bodies to Json, Form, Bytes or String extractors, or serve them to awc clients, causing denial of service.

Inefficient Algorithmic Complexity in hMailServer

Inefficient algorithmic complexity in the JSON reader of Progressive Robot hMailServer 6.3.6 and 6.3.7 allows a remote attacker to hold the server's mail delivery threads or its REST API's worker threads, making mail delivery, the REST API and the webmail unavailable. 6.3.6 fixed CVE-2026-107574, in which reading a JSON object searched the member names already read for each new name, by keeping the names in a hash set; the set uses the standard library's hash, which takes no secret, so member names chosen to fall in one bucket of it still cost time growing with the square of their number. Against the released reader, one such object of 16 MB took about 5 seconds to read in the Linux build, and one of under 6 MB about 23 seconds in the Windows build, where objects of the same sizes with other names took under a tenth of a second. A remote unauthenticated attacker reaches the reader by mailing such an object as a TLS-RPT report, up to 16 MB once decompressed, to a hosted domain's report mailbox, where an administrator has set one; it is read on a mail delivery thread (ten by default), and those threads deliver all mail, local and outbound, so a stream of such reports stops all delivery for as long as it continues. It is also reached without an account through the reply to a password-protected message, with the message's link alone, where the REST API is on (it is off by default) and a public base URL for such links is set; and by any account through the webmail's routes granted 16 MB, and by an application's API key through the send API. Each such request holds one of the REST API's four worker threads, in the process that also serves SMTP, IMAP and POP3.

fulgur: Unbounded string-set value accumulation causes memory/CPU exhaustion (denial of service)

fulgur converts untrusted HTML/CSS into PDF, commonly on a server that processes input supplied by many tenants. From version 0.4.4 to before version 0.29.0, the CSS string-set named-string values resolved from a document were accumulated per element with no memory budget, letting a small crafted document amplify into large retained memory (and the CPU to copy it) — results in a denial of service. This issue has been patched in version 0.29.0.

PapaParse before 5.7.1 Quadratic-Time Parsing DoS via indexOf Scan

PapaParse before 5.7.1 contains an inefficient algorithmic complexity vulnerability that allows remote unauthenticated attackers to cause denial of service by submitting delimiter-free quoted CSV input to Papa.parse(). Attackers can supply a single-column quoted CSV with no delimiters, triggering repeated full-buffer indexOf scans per row that grow quadratically with input size, exhausting CPU and blocking the Node.js event loop or freezing a browser tab.

proxygen's HTTP/3 codec buffered an incomplete non-DATA frame, such as a control-stream frame, a frame of an unknown or reserved type, or a HEADERS frame, until its entire declared length had arrived, without limiting that length, and re-scanned all buffered data each time more bytes arrived. A remote, unauthenticated HTTP/3 peer could declare a very large frame and deliver it slowly, causing unbounded memory growth and CPU usage that grows quadratically with the number of fragments, leading to denial of service. This issue affects proxygen versions prior to v2026.11.09.00.

fulgur: Unbounded counters() expansion in generated content causes memory/CPU exhaustion (denial of service)

fulgur converts untrusted HTML/CSS into PDF, commonly on a server that processes input supplied by many tenants. From version 0.15.0 to before version 0.27.0, resolving the CSS counters(name, sep) function in generated content was bounded neither in the size of a single expansion nor in the aggregate work across an element tree. An attacker able to submit HTML/CSS to a fulgur-based conversion service can trigger CPU and memory exhaustion with a trivially small payload, denying service to the host and any co-tenants. This issue has been patched in version 0.27.0.

fulgur: Quadratic style-list reprocessing during containing-block resolution for absolutely-positioned pseudo-elements causes denial of servicefulgur:

fulgur converts untrusted HTML/CSS into PDF, commonly on a server that processes input supplied by many tenants. From version 0.6.0 to before version 0.33.0, quadratic style-list reprocessing during containing-block resolution for absolutely-positioned pseudo-elements cause denial of service. This issue has been patched in version 0.33.0.

BACnet Stack: Channel member self-reference causes uncontrolled recursion and stack overflow in default BACnet/IP server

BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to versions 1.4.4 and 1.5.1, a remote attacker can trigger an uncontrolled recursion and stack overflow in the default server application of bacnet-stack by abusing the Channel object. This issue has been patched in versions 1.4.4 and 1.5.1.

Missing release of memory after effective lifetime vulnerability in openEuler iSulad on Linux. This vulnerability is associated with program file src/daemon/modules/spec/specs_mount.c. This issue affects iSulad: through 2.1.6. The memory leak vulnerability causes the iSulad daemon to be triggered frequently, exhausting the host machine's memory and ultimately leading to an OOM crash of the daemon, resulting in a denial of service (DoS).

Soup Sieve: Quadratic-time denial of service when matching `:has()`

Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 4.0.1, Soup Sieve repeatedly searches descendant subtrees for each candidate evaluated by :has() and repeatedly reevaluates a parent containing :has(> ...) for each child, causing quadratic matching on deeply nested or wide attacker-influenced HTML or XML. Applications using ordinary fixed selectors through select(), select_one(), or Beautiful Soup CSS APIs against untrusted documents can have a worker occupied for seconds or minutes, while applications that process only trusted documents are not affected. Selectors compiled with NOCACHE continue to use the old uncached behavior. This issue is fixed in version 4.0.1.

Soup Sieve: Polynomial-time denial of service in the descendant combinator

Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 4.0, Soup Sieve repeatedly walks the same ancestors while matching descendant combinators, and each additional descendant combinator raises the polynomial degree of the work on deeply nested attacker-influenced HTML or XML. Applications using selectors such as section div div through select(), select_one(), or Beautiful Soup CSS APIs against untrusted documents can have a worker occupied for seconds or minutes, while trusted-only document processing is not affected. Selectors compiled with NOCACHE continue to use the old uncached behavior. This issue is fixed in version 4.0.

Soup Sieve: General sibling combinator inside :has() matches untrusted HTML in quadratic time

Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 2.10, matching a developer-authored selector that places the general sibling combinator inside :has() repeatedly scans each candidate element's following siblings when the right-hand side is absent, producing quadratic work on attacker-controlled HTML. Applications that evaluate a fixed selector such as div:has(a ~ b) over untrusted markup can have a worker occupied for minutes by a small document, while the adjacent sibling form and trusted-only document processing are not affected in the same way. This issue is fixed in version 2.10.

Loofah: Regular expression denial of service in the SVG local-reference check

Loofah is a general library for manipulating and transforming HTML/XML documents and fragments, built on top of Nokogiri. Prior to 2.25.3, the Loofah HTML5 sanitizer checks href and xlink:href on elements in SVG_ALLOW_LOCAL_HREF with a regular expression whose line anchor and newline-matching whitespace cause an all-whitespace value to be rescanned from every line start. An attacker can submit an SVG reference element with a long multiline-whitespace attribute and consume CPU quadratically during sanitization. CRuby 3.1 and earlier and JRuby are affected, while CRuby 3.2 and later uses linear-time regular-expression matching. The default safelist reaches the vulnerable check without a configuration change. This issue is fixed in version 2.25.3.