{"items":[{"id":"NVI-00013974","kind":"vulnerability","title":"Mistune: Denial of Service — RecursionError via Excessive Emphasis Markers in Markdown","revision":3,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-6m44-fpc8-c3rq","CVE-2026-76098"],"plain_summary":"GitHub lists this reviewed advisory for mistune. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-0335c7398bfc66f59de26fa91e49a547"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-09-02T15:14:56.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-2a9a8df9bec058ae2611c64af14ccbf1"},{"kind":"EPSS","as_of":"2026-11-06T12:00:23.000Z","value":"0.488%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.42183. Missing scores are unknown.","source_id":"sr-0335c7398bfc66f59de26fa91e49a547"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-2a9a8df9bec058ae2611c64af14ccbf1","url":"https://github.com/advisories/GHSA-6m44-fpc8-c3rq","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-6m44-fpc8-c3rq","publisher":"GitHub Advisory Database","observed_at":"2026-11-02T02:21:43.711Z"},{"id":"sr-0335c7398bfc66f59de26fa91e49a547","url":"https://www.first.org/epss/data.html","basis":"official_catalog","notes":"FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.","title":"CVE-2026-76098","publisher":"FIRST EPSS","observed_at":"2026-11-07T00:50:47.053Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-2a9a8df9bec058ae2611c64af14ccbf1"],"technology":"mistune","known_exclusions":[],"conditions_summary":"## Summary\nMistune v3.3.2 is vulnerable to a Denial of Service (DoS) attack via uncontrolled recursion in the HTML rendering of deeply-nested emphasis tokens. By submitting Markdown containing approximately 1,000 consecutive asterisk characters, an attacker causes the Python process to crash with RecursionError.\n\n## Details\nThe InlineParser's _process_emphasis_delimiters() creates deeply nested  tokens from consecutive emphasis markers (every 2 asterisks add one nesting level). With 1,000 consecutive asterisks, approximately 500 levels of nesting are produced. The HTMLRenderer.render_token() method (src/mistune/renderers/html.py:40-57) renders these tokens recursively: when a token has children, line 48 calls self.render_tokens(token['children'], state), entering child rendering. Each nesting level produces ~2 stack frames, so 500 levels ≈ 1,000 frames, exceeding Python's default recursion limit (sys.getrecursionlimit() = 1000). The emphasis() and strong() methods (lines 80-84) wrap recursively rendered child content in  and  tags, perpetuating the recursion. This vulnerability affects all mistune APIs including markdown() and html().\n\nCore vulnerable code path:","public_affected_ranges":[">= 3.3.0, < 3.3.3"]}],"null_published_at":"2026-11-07T22:29:26.089Z","source_updated_at":"2026-09-02T15:14:56.000Z","source_disclosed_at":"2026-09-02T15:14:55.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.","null_first_observed_at":"2026-11-02T02:21:43.711Z"},{"id":"NVI-00013974","kind":"vulnerability","title":"Mistune: Denial of Service — RecursionError via Excessive Emphasis Markers in Markdown","revision":2,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-6m44-fpc8-c3rq","CVE-2026-76098"],"plain_summary":"GitHub lists this reviewed advisory for mistune. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-0c73c919cad25d2be1bf1d9e4f87b790"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-09-02T15:14:56.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-2a9a8df9bec058ae2611c64af14ccbf1"},{"kind":"EPSS","as_of":"2026-11-03T12:00:27.000Z","value":"0.488%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.42046. Missing scores are unknown.","source_id":"sr-0c73c919cad25d2be1bf1d9e4f87b790"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-2a9a8df9bec058ae2611c64af14ccbf1","url":"https://github.com/advisories/GHSA-6m44-fpc8-c3rq","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-6m44-fpc8-c3rq","publisher":"GitHub Advisory Database","observed_at":"2026-11-02T02:21:43.711Z"},{"id":"sr-0c73c919cad25d2be1bf1d9e4f87b790","url":"https://www.first.org/epss/data.html","basis":"official_catalog","notes":"FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.","title":"CVE-2026-76098","publisher":"FIRST EPSS","observed_at":"2026-11-03T17:45:16.081Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-2a9a8df9bec058ae2611c64af14ccbf1"],"technology":"mistune","known_exclusions":[],"conditions_summary":"## Summary\nMistune v3.3.2 is vulnerable to a Denial of Service (DoS) attack via uncontrolled recursion in the HTML rendering of deeply-nested emphasis tokens. By submitting Markdown containing approximately 1,000 consecutive asterisk characters, an attacker causes the Python process to crash with RecursionError.\n\n## Details\nThe InlineParser's _process_emphasis_delimiters() creates deeply nested  tokens from consecutive emphasis markers (every 2 asterisks add one nesting level). With 1,000 consecutive asterisks, approximately 500 levels of nesting are produced. The HTMLRenderer.render_token() method (src/mistune/renderers/html.py:40-57) renders these tokens recursively: when a token has children, line 48 calls self.render_tokens(token['children'], state), entering child rendering. Each nesting level produces ~2 stack frames, so 500 levels ≈ 1,000 frames, exceeding Python's default recursion limit (sys.getrecursionlimit() = 1000). The emphasis() and strong() methods (lines 80-84) wrap recursively rendered child content in  and  tags, perpetuating the recursion. This vulnerability affects all mistune APIs including markdown() and html().\n\nCore vulnerable code path:","public_affected_ranges":[">= 3.3.0, < 3.3.3"]}],"null_published_at":"2026-11-06T00:29:57.246Z","source_updated_at":"2026-09-02T15:14:56.000Z","source_disclosed_at":"2026-09-02T15:14:55.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.","null_first_observed_at":"2026-11-02T02:21:43.711Z"},{"id":"NVI-00013974","kind":"vulnerability","title":"Mistune: Denial of Service — RecursionError via Excessive Emphasis Markers in Markdown","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-6m44-fpc8-c3rq","CVE-2026-76098"],"plain_summary":"GitHub lists this reviewed advisory for mistune. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-2a9a8df9bec058ae2611c64af14ccbf1"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-09-02T15:14:56.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-2a9a8df9bec058ae2611c64af14ccbf1"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-2a9a8df9bec058ae2611c64af14ccbf1","url":"https://github.com/advisories/GHSA-6m44-fpc8-c3rq","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-6m44-fpc8-c3rq","publisher":"GitHub Advisory Database","observed_at":"2026-11-02T02:21:43.711Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-2a9a8df9bec058ae2611c64af14ccbf1"],"technology":"mistune","known_exclusions":[],"conditions_summary":"## Summary\nMistune v3.3.2 is vulnerable to a Denial of Service (DoS) attack via uncontrolled recursion in the HTML rendering of deeply-nested emphasis tokens. By submitting Markdown containing approximately 1,000 consecutive asterisk characters, an attacker causes the Python process to crash with RecursionError.\n\n## Details\nThe InlineParser's _process_emphasis_delimiters() creates deeply nested  tokens from consecutive emphasis markers (every 2 asterisks add one nesting level). With 1,000 consecutive asterisks, approximately 500 levels of nesting are produced. The HTMLRenderer.render_token() method (src/mistune/renderers/html.py:40-57) renders these tokens recursively: when a token has children, line 48 calls self.render_tokens(token['children'], state), entering child rendering. Each nesting level produces ~2 stack frames, so 500 levels ≈ 1,000 frames, exceeding Python's default recursion limit (sys.getrecursionlimit() = 1000). The emphasis() and strong() methods (lines 80-84) wrap recursively rendered child content in  and  tags, perpetuating the recursion. This vulnerability affects all mistune APIs including markdown() and html().\n\nCore vulnerable code path:","public_affected_ranges":[">= 3.3.0, < 3.3.3"]}],"null_published_at":"2026-11-02T10:00:37.193Z","source_updated_at":"2026-09-02T15:14:56.000Z","source_disclosed_at":"2026-09-02T15:14:55.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-11-02T02:21:43.711Z"}],"next_cursor":null,"snapshot_revision":"42594"}