Common Weakness Enumeration

CWE-1333

Inefficient Regular Expression Complexity

The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.

CVE-2026-59220 (GCVE-0-2026-59220)

Vulnerability from cvelistv5 – Published: 2026-07-09 16:09 – Updated: 2026-07-09 18:45
VLAI
Title
Open WebUI: ReDoS in skill-mention regexes causes whole-instance DoS on default config
Summary
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.2 before 0.10.0, the SKILL_MENTION_RE and strip_re regular expressions in backend/open_webui/utils/middleware.py parsed <$skillId|label> skill mentions with overlapping quantifiers, allowing an authenticated chat message containing <$ without a closing > to trigger quadratic backtracking and block the asyncio event loop. This issue is fixed in version 0.10.0.
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-1333 - Inefficient Regular Expression Complexity
Assigner
Impacted products
Vendor Product Version
open-webui open-webui Affected: >= 0.9.2, < 0.10.0
Create a notification for this product.
Show details on NVD website

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CVE-2026-5986 (GCVE-0-2026-5986)

Vulnerability from cvelistv5 – Published: 2026-04-09 22:30 – Updated: 2026-04-14 03:12
VLAI
Title
Zod jsVideoUrlParser util.js getTime redos
Summary
A weakness has been identified in Zod jsVideoUrlParser up to 0.5.1. The impacted element is the function getTime in the library lib/util.js. This manipulation of the argument timestamp causes inefficient regular expression complexity. It is possible to initiate the attack remotely. The exploit has been made available to the public and could be used for attacks. The project was informed of the problem early through an issue report but has not responded yet.
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-1333 - Inefficient Regular Expression Complexity
  • CWE-400 - Resource Consumption
Assigner
References
URL Tags
https://vuldb.com/vuln/356540 vdb-entrytechnical-description
https://vuldb.com/vuln/356540/cti signaturepermissions-required
https://vuldb.com/submit/791911 third-party-advisory
https://github.com/Zod-/jsVideoUrlParser/issues/121 issue-tracking
https://github.com/Zod-/jsVideoUrlParser/issues/1… exploitissue-tracking
Impacted products
Vendor Product Version
Zod jsVideoUrlParser Affected: 0.5.0
Affected: 0.5.1
Create a notification for this product.
Credits
ybdesire (VulDB User) VulDB CNA Team
Show details on NVD website

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CVE-2026-59922 (GCVE-0-2026-59922)

Vulnerability from cvelistv5 – Published: 2026-07-08 16:12 – Updated: 2026-07-09 14:40
VLAI
Title
Mistune plugins/formatting: quadratic-time parsing on long runs of `~~x~~`, `==x==`, and `^^x^^` markers (strikethrough / mark / insert)
Summary
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, a run of closed tilde, equals-sign, or caret marker pairs around a character causes quadratic work in src/mistune/plugins/formatting.py when the strikethrough, mark, or insert plugin scans for matching markers from each possible start position, allowing denial of service through CPU exhaustion. This issue is fixed in version 3.3.0.
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
  • CWE-1333 - Inefficient Regular Expression Complexity
Assigner
Impacted products
Vendor Product Version
lepture mistune Affected: < 3.3.0
Create a notification for this product.
Show details on NVD website

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CVE-2026-59925 (GCVE-0-2026-59925)

Vulnerability from cvelistv5 – Published: 2026-07-08 16:18 – Updated: 2026-07-08 19:44
VLAI
Title
inline_parser: quadratic-time parsing on long runs of `**x**` and `***x***` emphasis pairs
Summary
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, long sequences of well-formed double-asterisk or triple-asterisk emphasis pairs around a character cause quadratic work in src/mistune/inline_parser.py because the parser scans forward for matching close markers from every potential opening run, allowing denial of service in default Mistune parsing. This issue is fixed in version 3.3.0.
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
  • CWE-1333 - Inefficient Regular Expression Complexity
Assigner
Impacted products
Vendor Product Version
lepture mistune Affected: < 3.3.0
Create a notification for this product.
Show details on NVD website

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CVE-2026-59928 (GCVE-0-2026-59928)

Vulnerability from cvelistv5 – Published: 2026-07-08 16:23 – Updated: 2026-07-08 19:40
VLAI
Title
Mistune block_parser: quadratic-time parsing on long lists of repeated reference-link definitions
Summary
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, a Markdown document containing many repeated or distinct reference-link definitions causes quadratic work in src/mistune/block_parser.py and the ref_links environment dictionary handling, allowing denial of service through CPU exhaustion. This issue is fixed in version 3.3.0.
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
  • CWE-1333 - Inefficient Regular Expression Complexity
Assigner
Impacted products
Vendor Product Version
lepture mistune Affected: < 3.3.0
Create a notification for this product.
Show details on NVD website

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CVE-2026-8159 (GCVE-0-2026-8159)

Vulnerability from cvelistv5 – Published: 2026-05-12 08:35 – Updated: 2026-05-12 12:33
VLAI
Title
multiparty vulnerable to ReDoS via filename parsing
Summary
multiparty@4.2.3 and lower versions are vulnerable to denial of service via regular expression backtracking in the Content-Disposition filename parameter parser. A crafted multipart upload with a long header value can cause regex matching to take seconds, blocking the event loop. Impact: any service accepting multipart uploads via multiparty is affected. Workarounds: limiting upload sizes at the proxy or gateway layer reduces but does not eliminate the attack surface, since a small header of around 8 KB is sufficient to trigger the vulnerable backtracking. Upgrade to multiparty@4.3.0 or higher.
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-1333 - Inefficient Regular Expression Complexity
Assigner
Impacted products
Vendor Product Version
multiparty multiparty Affected: 0 , ≤ 4.2.3 (semver)
Unaffected: 4.3.0 (semver)
Create a notification for this product.
Credits
aszx87410 Blake Embrey Ulises Gascón
Show details on NVD website

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Mitigation

Phase: Architecture and Design

Description:

  • Use regular expressions that do not support backtracking, e.g. by removing nested quantifiers.
Mitigation

Phase: System Configuration

Description:

  • Set backtracking limits in the configuration of the regular expression implementation, such as PHP's pcre.backtrack_limit. Also consider limits on execution time for the process.
Mitigation

Phase: Implementation

Description:

  • Do not use regular expressions with untrusted input. If regular expressions must be used, avoid using backtracking in the expression.
Mitigation

Phase: Implementation

Description:

  • Limit the length of the input that the regular expression will process.
CAPEC-492: Regular Expression Exponential Blowup

An adversary may execute an attack on a program that uses a poor Regular Expression(Regex) implementation by choosing input that results in an extreme situation for the Regex. A typical extreme situation operates at exponential time compared to the input size. This is due to most implementations using a Nondeterministic Finite Automaton(NFA) state machine to be built by the Regex algorithm since NFA allows backtracking and thus more complex regular expressions.

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