CVE-2026-6850
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to validate the length and content of message attachment fi
CVSS
6.5
Medium
EPSS
0.2%
p15
KEV
—
Exploit Today
5
0-100
Published: Jul 13, 2026 · Last modified: Jul 13, 2026 · CWE-1333
0.2%EPSS · 30 days0.2%
2026-07-132026-07-18
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to validate the length and content of message attachment field values, which allows an authenticated attacker to cause a denial of service for all users in a channel via a post containing a specially crafted payload that triggers catastrophic backtracking in the client-side markdown parser.. Mattermost Advisory ID: MMSA-2026-00658
CVECVSSEPSSKEVRExploitTitleMod.
CVE-2022-421247.5 HIG65.6%
——20ReDoS vulnerability in LayoutPageTemplateEntryUpgradeProcess in Liferay Portal 7.3.2 through 7.4.3.4 and Liferay DXP 7.2 fix pack 9 through fix pack 18, 7.3 before update 4, and DXP 7.4 GA allows remote attackers to consume an excessive amount of server resources via a crafted payload injected into the 'name' field of a layout prototype.10dCVE-2026-49267.5 HIG52.2%
——16Impact:
A bad regular expression is generated any time you have multiple sequential optional groups (curly brace syntax), such as `{a}{b}{c}:z`. The generated regex grows exponentially with the number of groups, causing denial of service.
Patches:
Fixed in version 8.4.0.
Workarounds:
Limit the number of sequential optional groups in route patterns. Avoid passing user-controlled input as route patterns.2dCVE-2026-453057.5 HIG50.8%
——15Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12, Symfony\Component\Yaml\Parser::cleanup() used regular expressions with overlapping quantifiers for YAML directive, comment, and document marker cleanup, allowing crafted input to make parsing hang for an arbitrarily long time. This issue is fixed in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.4dCVE-2024-462427.5 HIG49.2%
——15An issue in the validate_email function in CTFd/utils/validators/__init__.py of CTFd 3.7.3 allows attackers to cause a Regular expression Denial of Service (ReDoS) via supplying a crafted string as e-mail address during registration.14dCVE-2026-283567.5 HIG49.0%
——15multipart is a fast multipart/form-data parser for python. Prior to 1.2.2, 1.3.1 and 1.4.0-dev, the parse_options_header() function in multipart.py uses a regular expression with an ambiguous alternation, which can cause exponential backtracking (ReDoS) when parsing maliciously crafted HTTP or multipart segment headers. This can be abused for denial of service (DoS) attacks against web applications using this library to parse request headers or multipart/form-data streams. The issue is fixed in 1.2.2, 1.3.1 and 1.4.0-dev.4dCVE-2026-451337.5 HIG48.7%
——15Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12, when the parser is exposed to attacker-controlled input, deeply nested mappings or sequences cause both the block-level (Parser::parseBlock()) and inline (Inline::parseSequence() / Inline::parseMapping()) parsers to recurse without a depth limit. A crafted document exhausts the PHP stack and crashes the worker. This issue is fixed in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.4d