{"items":[{"id":"NVI-00010603","kind":"vulnerability","title":"Twisted: Denial of Service in the Twisted IMAP4 Server via a Negative Literal Size in SEARCH","revision":2,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-2qrf-pqgx-qh9v","CVE-2026-115774"],"plain_summary":"GitHub lists this reviewed advisory for Twisted. 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-4a6f9dc00994dec53417518582cbc208"],"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":"2026-10-23T20:46:13.000Z","value":"4.9 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-661fc977cdcb3658272b4a3b0e572de8"},{"kind":"EPSS","as_of":"2026-10-31T12:00:27.000Z","value":"0.520%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.44218. Missing scores are unknown.","source_id":"sr-4a6f9dc00994dec53417518582cbc208"}],"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-661fc977cdcb3658272b4a3b0e572de8","url":"https://github.com/advisories/GHSA-2qrf-pqgx-qh9v","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-2qrf-pqgx-qh9v","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T22:07:08.657Z"},{"id":"sr-4a6f9dc00994dec53417518582cbc208","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-2026-115774","publisher":"FIRST EPSS","observed_at":"2026-10-31T23:13:27.689Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-661fc977cdcb3658272b4a3b0e572de8"],"technology":"Twisted","known_exclusions":[],"conditions_summary":"## Summary\n\nAn infinite-loop vulnerability (CWE-835) in the Twisted IMAP4 server lets an authenticated client freeze the whole process with one small command. `twisted.mail.imap4.parseNestedParens` reads an IMAP literal size with `int()` and never rejects a negative value. A negative size such as `{-100}` drives the parser cursor negative, and because a negative Python index wraps around the end of the string instead of raising, the scanning loop never terminates. It runs synchronously on the single-threaded reactor, so one `SEARCH` command holds the reactor at full CPU forever and every other connection stops being served.\n\n## Details\n\nMeeting an inline literal, `parseNestedParens` reads the size between the braces and advances the cursor past the body:\n\n```python\n# twisted/mail/imap4.py  parseNestedParens\nliteralSize = int(s[i + 1 : end])          # no sign check\ncontentStack[-1].append((s[end + 3 : end + 3 + literalSize],))\ni = end + 3 + literalSize                    # negative size -> i goes negative\n```\n\n`int(b\"-100\")` is `-100`, so `i` goes negative; the loop condition `i < len(s)` stays true and `s[i : i + 1]` on a negative index never raises, so the cursor cycles forever. ","public_affected_ranges":["<= 26.4.0"]}],"null_published_at":"2026-11-01T07:29:08.034Z","source_updated_at":"2026-10-23T20:46:13.000Z","source_disclosed_at":"2026-10-23T20:46:12.000Z","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":"2026-10-31T22:07:08.657Z"},{"id":"NVI-00010603","kind":"vulnerability","title":"Twisted: Denial of Service in the Twisted IMAP4 Server via a Negative Literal Size in SEARCH","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-2qrf-pqgx-qh9v","CVE-2026-115774"],"plain_summary":"GitHub lists this reviewed advisory for Twisted. 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-661fc977cdcb3658272b4a3b0e572de8"],"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":"2026-10-23T20:46:13.000Z","value":"4.9 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-661fc977cdcb3658272b4a3b0e572de8"}],"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-661fc977cdcb3658272b4a3b0e572de8","url":"https://github.com/advisories/GHSA-2qrf-pqgx-qh9v","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-2qrf-pqgx-qh9v","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T22:07:08.657Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-661fc977cdcb3658272b4a3b0e572de8"],"technology":"Twisted","known_exclusions":[],"conditions_summary":"## Summary\n\nAn infinite-loop vulnerability (CWE-835) in the Twisted IMAP4 server lets an authenticated client freeze the whole process with one small command. `twisted.mail.imap4.parseNestedParens` reads an IMAP literal size with `int()` and never rejects a negative value. A negative size such as `{-100}` drives the parser cursor negative, and because a negative Python index wraps around the end of the string instead of raising, the scanning loop never terminates. It runs synchronously on the single-threaded reactor, so one `SEARCH` command holds the reactor at full CPU forever and every other connection stops being served.\n\n## Details\n\nMeeting an inline literal, `parseNestedParens` reads the size between the braces and advances the cursor past the body:\n\n```python\n# twisted/mail/imap4.py  parseNestedParens\nliteralSize = int(s[i + 1 : end])          # no sign check\ncontentStack[-1].append((s[end + 3 : end + 3 + literalSize],))\ni = end + 3 + literalSize                    # negative size -> i goes negative\n```\n\n`int(b\"-100\")` is `-100`, so `i` goes negative; the loop condition `i < len(s)` stays true and `s[i : i + 1]` on a negative index never raises, so the cursor cycles forever. ","public_affected_ranges":["<= 26.4.0"]}],"null_published_at":"2026-10-31T22:27:09.625Z","source_updated_at":"2026-10-23T20:46:13.000Z","source_disclosed_at":"2026-10-23T20:46:12.000Z","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":"2026-10-31T22:07:08.657Z"}],"next_cursor":null,"snapshot_revision":"42594"}