PYSEC-2026-3883 plone.app.event vulnerable to denial of service via iCalendar import

Impact By abusing the iCalendar import functionality, a logged-in editor could take the whole site offline, make the server reach into the internal network and read calendar files off disk SSRF, and store XSS. Patches The problem has been patched in plone.app.event. For Plone 6.2: upgrade to...

PYSEC-2026-3853 JupyterHub has Unauthenticated Denial of Service via Unbounded Username Logging on Failed Login

Impact Invalid input to login resulted in unbounded logging output. Only form-based Authenticators the default PAM Authenticator, but not the more widely used OAuthenticator are affected. Patches Upgrade to 5.5.0. Workarounds Use an Authenticator that doesn't use a login form, such as...

JupyterHub has Unauthenticated Denial of Service via Unbounded Username Logging on Failed Login

ImpactInvalid input to login resulted in unbounded logging output. Only form-based Authenticators the default PAM Authenticator, but not the more widely used OAuthenticator are affected. PatchesUpgrade to 5.5.0. WorkaroundsUse an Authenticator that doesn't use a login form, such as OAuthenticator...

icalendar has Algorithmic Complexity in Equality

SummaryComponent.eq compares subcomponents in O2^n time relative to nesting depth. Because the parser accepts arbitrarily nested components, a sub-kilobyte .ics file is enough to make a single equality check run for minutes or hang indefinitely. Any application that compares parsed components ==,...

PYSEC-2026-3851 icalendar has Algorithmic Complexity in Equality

Summary Component.eq compares subcomponents in O2^n time relative to nesting depth. Because the parser accepts arbitrarily nested components, a sub-kilobyte .ics file is enough to make a single equality check run for minutes or hang indefinitely. Any application that compares parsed components ==...

Starlette-Admin's unvalidated `order_by` parameter allows ordering by hidden columns (info-exposure oracle) and HTTP 500 DoS

SummaryAffected versions of Starlette-Admin prior to 0.16.1 do not properly validate user-supplied sort and search parameters against the configured field allowlists. While the administrative UI restricts available fields based on field configuration, the backend accepts arbitrary field names...

eml_parser has parser DoS via deeply nested parentheses in e-mail headers

Summaryemlparser uses the email.utils.getaddresses function from the CPython standard library to parse e-mail headers that contain e-mail addresses such as To, Cc, Bcc, From, Reply-To, Sender, .... When the input header contains a deeply nested CFWS comment / folding white space construct, the...

eml_parser vulnerable to DoS via deeply nested parens in Received headers

Summaryemlparser strips parenthesised CFWS comments from Received: headers using a regex-based fix-point loop. The loop has quadratic time complexity in the number of nested parens. A single Received: header containing 5,000 nested parens causes 1.3 seconds of CPU saturation per parsed message;...

PYSEC-2026-3832 eml_parser vulnerable to DoS via deeply nested parens in Received headers

Summary emlparser strips parenthesised CFWS comments from Received: headers using a regex-based fix-point loop. The loop has quadratic time complexity in the number of nested parens. A single Received: header containing 5,000 nested parens causes 1.3 seconds of CPU saturation per parsed message;...

PYSEC-2026-3905 praisonaiagents has an SSRF protection bypass in `spider_tools._host_is_blocked()` via DNS-resolved hostnames (`127.0.0.1.nip.io`)

Summary praisonaiagents/tools/spidertools.py contains an SSRF protection bypass. The function hostisblocked validates URLs against a list of blocked IP literals and hostname aliases, but never performs DNS resolution. Any hostname that resolves to a private or loopback IP address — including publ...

django CMS: Plugin move endpoint allows cyclic reparenting (DoS)

SummaryThe moveplugin admin endpoint does not prevent a plugin from being reparented under itself or one of its own descendants. Doing so creates a cycle in the plugin tree, after which the recursive descendant/ancestor SQL queries loop without terminating, stalling the request worker...

PYSEC-2026-3822 django CMS: Plugin move endpoint allows cyclic reparenting (DoS)

Summary The moveplugin admin endpoint does not prevent a plugin from being reparented under itself or one of its own descendants. Doing so creates a cycle in the plugin tree, after which the recursive descendant/ancestor SQL queries loop without terminating, stalling the request worker. Details...

NLTK TweetTokenizer vulnerable to denial of service through catastrophic regex backtracking

The URLS regular expression in nltk/tokenize/casual.py, compiled into TweetTokenizer.WORDRE and applied by TweetTokenizer.tokenize, contains a naked-domain branch whose domain-label prefix a-z0-9+?:.\-a-z0-9+ is unbounded. Input consisting of many alternating label separators can be partitioned i...

PYSEC-2026-3870 NLTK TweetTokenizer vulnerable to denial of service through catastrophic regex backtracking

The URLS regular expression in nltk/tokenize/casual.py, compiled into TweetTokenizer.WORDRE and applied by TweetTokenizer.tokenize, contains a naked-domain branch whose domain-label prefix a-z0-9+?:.-a-z0-9+ is unbounded. Input consisting of many alternating label separators can be partitioned in...

Accelerate path traversal and denial of service via sharded checkpoint weight_map entries

Hugging Face Accelerate through 1.14.0 contains a path traversal vulnerability in loadcheckpointinmodel and loadcheckpointanddispatch functions that fail to sanitize weightmap entries from sharded checkpoint indexes. Attackers can supply relative paths with ../ sequences or absolute paths to read...

PYSEC-2026-3865 MLflow AI Gateway permits SSRF through an unvalidated api_base

MLflow's AI Gateway accepts an authconfig.apibase value when creating a gateway secret mlflow/server/handlers.py, creategatewaysecret with no validation of scheme, host, or IP range; the value is stored verbatim. The gateway proxy endpoint mlflow/server/gatewayapi.py, rawproxy subsequently issues...

PYSEC-2026-3856 Keras model loading is vulnerable to denial of service through HDF5 shape bombs

A vulnerability in keras-team/keras versions 3.15.0 allows for a denial of service DoS attack when loading malicious .keras model files via the keras.models.loadmodel function. The H5IOStore.getitem method in keras/src/saving/savinglib.py does not validate the shape or size of datasets, leading t...

Keras model loading is vulnerable to denial of service through HDF5 shape bombs

A vulnerability in keras-team/keras versions 3.15.0 allows for a denial of service DoS attack when loading malicious .keras model files via the keras.models.loadmodel function. The H5IOStore.getitem method in keras/src/saving/savinglib.py does not validate the shape or size of datasets, leading t...

PYSEC-2026-3804 Accelerate path traversal and denial of service via sharded checkpoint weight_map entries

Hugging Face Accelerate through 1.14.0 contains a path traversal vulnerability in loadcheckpointinmodel and loadcheckpointanddispatch functions that fail to sanitize weightmap entries from sharded checkpoint indexes. Attackers can supply relative paths with ../ sequences or absolute paths to read...

Uncontrolled recursion DoS in JustHTML() via deeply nested HTML

Summaryjusthtml through 1.9.1 allows denial of service via deeply nested HTML. During parsing, JustHTML.init always reaches TreeBuilder.finish, which unconditionally calls populateselectedcontent. That function recursively traverses the DOM via findelements / findelement without a depth bound,...