DailyCVE@dailycve
🔴 league/commonmark, Quadratic Complexity DoS, #CVE-2026-33347 (High) -DC-Sep2026-2678 https://dailycve.com/league-commonmark-quadratic-complexity-dos-cve-2026-33347-high-dc-sep2026-2678/
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CVE-2026-33347(thephpleague / commonmark)
LOWCVSS 6.1 · MEDIUMSignal is active with 1 mentions in latest observed window
Immediate actions
- Track advisory updates for patch or workaround availability
Recommended action window: Monitor and triage in normal cycle
NVD description
league/commonmark is a PHP Markdown parser. From version 2.3.0 to before version 2.8.2, the DomainFilteringAdapter in the Embed extension is vulnerable to an allowlist bypass due to a missing hostname boundary assertion in the domain-matching regex. An attacker-controlled domain like youtube.com.evil passes the allowlist check when youtube.com is an allowed domain. This issue has been patched in version 2.8.2.
0.0/ 10 priority
Sources & remediation
Patch / fix
Vendor / third-party advisories
Other references
Weakness type (CWE)
CWE-79CWE-185CWE-918
Priority
LOW
Exploitation
NONE
PoC
NONE
Patch
AVAILABLE
Momentum
NONE
Are you affected?
If you run products in this scope, you should treat this CVE as relevant to your environment.
- commonmark
Threat summary
- 1 mentions across 1 observed day
What's happening
- 1 total mentions across 1 day
Affected systems
Vendors
Products
commonmark
Deep dive
Activity timeline1 mentions / 1d
Referenced assets1 URL
Full discourse1 post
CPE platform detail1 entries
1 of 1 entries
| Part | Vendor | Product | Version | Target SW | Target HW |
|---|---|---|---|---|---|
| App | thephpleague | commonmark | - | - | - |