CWE-674

{
  "affected": [],
  "aliases": [
    "CVE-2017-0886"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400",
      "CWE-674"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2017-04-05T20:59:00Z",
    "severity": "MODERATE"
  },
  "details": "Nextcloud Server before 9.0.55 and 10.0.2 suffers from a Denial of Service attack. Due to an error in the application logic an authenticated adversary may trigger an endless recursion in the application leading to a potential Denial of Service.",
  "id": "GHSA-cpjv-m49g-h8m9",
  "modified": "2022-05-13T01:38:26Z",
  "published": "2022-05-13T01:38:26Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2017-0886"
    },
    {
      "type": "WEB",
      "url": "https://hackerone.com/reports/174524"
    },
    {
      "type": "WEB",
      "url": "https://nextcloud.com/security/advisory/?id=nc-sa-2017-004"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

{
  "affected": [],
  "aliases": [
    "CVE-2022-47374"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-674"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-12-12T12:15:10Z",
    "severity": "HIGH"
  },
  "details": "A vulnerability has been identified in SIMATIC\u00a0PC-Station Plus (All versions), SIMATIC S7-400 CPU 412-2 PN V7 (All versions), SIMATIC S7-400 CPU 414-3 PN/DP V7 (All versions), SIMATIC S7-400 CPU 414F-3 PN/DP V7 (All versions), SIMATIC S7-400 CPU 416-3 PN/DP V7 (All versions), SIMATIC S7-400 CPU 416F-3 PN/DP V7 (All versions), SINAMICS S120 (incl. SIPLUS variants) (All versions \u003c V5.2 SP3 HF15), SIPLUS S7-400 CPU 414-3 PN/DP V7 (All versions), SIPLUS S7-400 CPU 416-3 PN/DP V7 (All versions). The affected products do not handle HTTP(S) requests to the web server correctly.\n\nThis could allow an attacker to exhaust system resources and create a denial of service condition for the device.",
  "id": "GHSA-cr2v-p345-fp24",
  "modified": "2023-12-12T12:30:53Z",
  "published": "2023-12-12T12:30:53Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-47374"
    },
    {
      "type": "WEB",
      "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-892915.pdf"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

{
  "affected": [],
  "aliases": [
    "CVE-2024-7866"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-674"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-08-15T20:15:18Z",
    "severity": "LOW"
  },
  "details": "In Xpdf 4.05 (and earlier), a PDF object loop in a pattern resource leads to infinite recursion and a stack overflow.",
  "id": "GHSA-cr4v-6m54-7vh3",
  "modified": "2024-08-20T21:30:32Z",
  "published": "2024-08-15T21:31:20Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-7866"
    },
    {
      "type": "WEB",
      "url": "https://www.xpdfreader.com/security-bug/object-loops.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "exiv2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.16.0"
            },
            {
              "fixed": "0.16.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2024-25112"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400",
      "CWE-674"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-10-17T17:13:24Z",
    "nvd_published_at": "2024-02-12T23:15:08Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\nA denial-of-service was found in Exiv2 version v0.28.1: an unbounded recursion can cause Exiv2 to crash by exhausting the stack. The vulnerable function, `QuickTimeVideo::multipleEntriesDecoder`, was new in v0.28.0 (see https://github.com/Exiv2/exiv2/pull/2337), so Exiv2 versions before v0.28 are _not_ affected.  Exiv2 is a command-line utility and C++ library for reading, writing, deleting, and modifying the metadata of image files. The denial-of-service is triggered when Exiv2 is used to read the metadata of a crafted video file.\n\n### Patches\nThe bug is fixed in version v0.28.2.\n\n### For more information\nPlease see our [security policy](https://github.com/Exiv2/exiv2/security/policy) for information about Exiv2 security.\n\n### Credit\nThis bug was found by [OSS-Fuzz](https://github.com/google/oss-fuzz).",
  "id": "GHSA-crmj-qh74-2r36",
  "modified": "2024-10-23T17:40:19Z",
  "published": "2024-10-17T17:13:24Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/Exiv2/exiv2/security/advisories/GHSA-crmj-qh74-2r36"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-25112"
    },
    {
      "type": "WEB",
      "url": "https://github.com/Exiv2/exiv2/pull/2337"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/Exiv2/exiv2"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/exiv2/PYSEC-2024-107.yaml"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Exiv2  has a denial of service due to unbounded recursion in QuickTimeVideo::multipleEntriesDecoder"
}

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "nltk"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "3.9.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-674"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-09-02T15:33:17Z",
    "nvd_published_at": "2026-08-22T15:16:19Z",
    "severity": "HIGH"
  },
  "details": "## Duplicate Advisory\n\nThis advisory has been withdrawn because it is a duplicate of\u00a0GHSA-rf74-v2fm-23pw. This link is maintained to preserve external references.\n\n## Original Description\nNLTK versions before 3.9.4 contain an unbounded recursion vulnerability in JSONTaggedDecoder.decode_obj() that allows attackers to cause denial of service by supplying deeply nested JSON structures. Attackers can craft JSON payloads exceeding the recursion limit to trigger an unhandled RecursionError that crashes the Python process.",
  "id": "GHSA-cv2g-m8rr-888c",
  "modified": "2026-09-02T15:33:17Z",
  "published": "2026-08-22T15:31:03Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/nltk/nltk/security/advisories/GHSA-rf74-v2fm-23pw"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-66393"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/nltk/nltk"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/nltk-before-denial-of-service-via-jsontaggeddecoder"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Duplicate Advisory: Natural Language Toolkit (NLTK) has unbounded recursion in JSONTaggedDecoder.decode_obj() may cause DoS",
  "withdrawn": "2026-09-02T15:33:17Z"
}

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "katex"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.15.4"
            },
            {
              "fixed": "0.16.10"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2024-28244"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-606",
      "CWE-674"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-03-25T19:38:29Z",
    "nvd_published_at": "2024-03-25T20:15:08Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\nKaTeX users who render untrusted mathematical expressions could encounter malicious input using `\\def` or `\\newcommand` that causes a near-infinite loop, despite setting `maxExpand` to avoid such loops. This can be used as an availability attack, where e.g. a client rendering another user\u0027s KaTeX input will be unable to use the site due to memory overflow, tying up the main thread, or stack overflow.\n\n### Patches\nUpgrade to KaTeX v0.16.10 to remove this vulnerability.\n\n### Workarounds\nForbid inputs containing any of the characters `\u208a\u208b\u208c\u208d\u208e\u2080\u2081\u2082\u2083\u2084\u2085\u2086\u2087\u2088\u2089\u2090\u2091\u2095\u1d62\u2c7c\u2096\u2097\u2098\u2099\u2092\u209a\u1d63\u209b\u209c\u1d64\u1d65\u2093\u1d66\u1d67\u1d68\u1d69\u1d6a\u207a\u207b\u207c\u207d\u207e\u2070\u00b9\u00b2\u00b3\u2074\u2075\u2076\u2077\u2078\u2079\u1d43\u1d47\u1d9c\u1d48\u1d49\u1d4d\u02b0\u2071\u02b2\u1d4f\u02e1\u1d50\u207f\u1d52\u1d56\u02b3\u02e2\u1d57\u1d58\u02b7\u02e3\u02b8\u1dbb\u1d5b\u1d5d\u1d5e\u1d5f\u1d60\u1d61` before passing them to KaTeX.\n(There is no easy workaround for the auto-render extension.)\n\n### Details\nKaTeX supports an option named `maxExpand` which aims to prevent infinitely recursive macros from consuming all available memory and/or triggering a stack overflow error. Unfortunately, [support for \"Unicode (sub|super)script characters\"](https://github.com/KaTeX/KaTeX/commit/d8fc35e6a97f8e561c723b93ad275cf5a7f3094a) allows an attacker to bypass this limit. Each sub/superscript group instantiated a separate Parser with its own limit on macro executions, without inheriting the current count of macro executions from its parent. This has been corrected in KaTeX v0.16.10.\n\n### For more information\nIf you have any questions or comments about this advisory:\n* Open an issue or security advisory in the [KaTeX repository](https://github.com/KaTeX/KaTeX/)\n* Email us at [katex-security@mit.edu](mailto:katex-security@mit.edu)",
  "id": "GHSA-cvr6-37gx-v8wc",
  "modified": "2024-03-25T22:32:01Z",
  "published": "2024-03-25T19:38:29Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/KaTeX/KaTeX/security/advisories/GHSA-cvr6-37gx-v8wc"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-28244"
    },
    {
      "type": "WEB",
      "url": "https://github.com/KaTeX/KaTeX/commit/085e21b5da05414efefa932570e7201a7c70e5b2"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/KaTeX/KaTeX"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "KaTeX\u0027s maxExpand bypassed by Unicode sub/superscripts"
}

{
  "affected": [],
  "aliases": [
    "CVE-2017-9304"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-674"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2017-05-31T04:29:00Z",
    "severity": "HIGH"
  },
  "details": "libyara/re.c in the regexp module in YARA 3.5.0 allows remote attackers to cause a denial of service (stack consumption) via a crafted rule that is mishandled in the _yr_re_emit function.",
  "id": "GHSA-cvvq-777c-65v4",
  "modified": "2022-05-13T01:47:53Z",
  "published": "2022-05-13T01:47:53Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2017-9304"
    },
    {
      "type": "WEB",
      "url": "https://github.com/VirusTotal/yara/issues/674"
    },
    {
      "type": "WEB",
      "url": "https://github.com/VirusTotal/yara/commit/925bcf3c3b0a28b5b78e25d9efda5c0bf27ae699"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 3.10.2"
      },
      "package": {
        "ecosystem": "PyPI",
        "name": "nltk"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.10.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-81724"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-674"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-09-02T14:33:22Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "### Summary\n\n`nltk.featstruct.FeatStructReader` (used by `FeatStruct(str)` and by `FeatureGrammar.fromstring()`) parses feature-structure strings such as `[a=1]` with a recursive-descent parser that has no nesting-depth limit. A small, trivially-crafted input (~700 bytes) with deeply nested brackets drives the parser past Python\u0027s recursion limit and raises an **unhandled `RecursionError`** instead of the library\u0027s normal, catchable `ValueError`/`LogicalExpressionException`. Any application that parses user-supplied feature-structure or feature-grammar text (e.g. NLP teaching tools, grammar \"playgrounds\", unification-grammar-based NLU pipelines) can be crashed by an unauthenticated input with no special privileges. This is a Denial of Service issue (CWE-674, Uncontrolled Recursion), not a memory-safety or code-execution issue.\n\nThis appears to be the same bug class as two issues already fixed elsewhere in the codebase \u2014 `nltk/jsontags.py` (`JSONTaggedDecoder.decode_obj`, guarded by `MAX_DECODE_DEPTH = 200`) and `nltk/sem/logic.py` (`LogicParser`, guarded by `MAX_PARSE_DEPTH = 200`) \u2014 but `nltk/featstruct.py` does not have an equivalent guard.\n\n### Details\n\nThe recursive call chain (current `develop` branch, `nltk/featstruct.py`):\n\n1. `FeatStructReader.fromstring()` ([`featstruct.py:2184`](nltk/featstruct.py#L2184)) calls `read_partial()` \u2192 `_read_partial()` ([`featstruct.py:2250`](nltk/featstruct.py#L2250)).\n2. `_read_partial()` dispatches to `_read_partial_featdict()`, which calls `_read_value()` ([`featstruct.py:2436`](nltk/featstruct.py#L2436)) for each feature\u0027s value.\n3. `_read_value()` calls `read_value()` ([`featstruct.py:2442`](nltk/featstruct.py#L2442)), which matches the value against `VALUE_HANDLERS` ([`featstruct.py:2478`](nltk/featstruct.py#L2478)).\n4. If the value itself starts with `[` (a nested feature structure), the matched handler is `read_fstruct_value` ([`featstruct.py:2479`](nltk/featstruct.py#L2479), defined at [`featstruct.py:2495`](nltk/featstruct.py#L2495)):\n   ```python\n   def read_fstruct_value(self, s, position, reentrances, match):\n       return self.read_partial(s, position, reentrances)\n   ```\n   This calls `read_partial()` again, which re-enters `_read_partial()` \u2014 the same function from step 1.\n\nThis closes a recursive cycle (`_read_partial \u2192 _read_value \u2192 read_value \u2192 read_fstruct_value \u2192 read_partial \u2192 _read_partial \u2192 ...`) with **no depth counter, no `MAX_*_DEPTH` constant, and no `try/except RecursionError`** anywhere in the class. Each additional `[` in the input adds one more full cycle of Python stack frames. Once the input nests deeply enough, Python\u0027s own recursion-limit protection fires and raises `RecursionError`, which is not a subclass of `ValueError` (the exception type this parser\u0027s own `_error()` helper raises for normal, well-formed parse errors) and therefore propagates uncaught through this API.\n\nFor comparison, `nltk/sem/logic.py`\u0027s `LogicParser` was hardened against exactly this class of issue:\n```python\n#: Maximum expression-nesting depth the recursive-descent parser will\n#: descend to. Deeply nested input would otherwise recurse until Python\n#: raises an uncaught RecursionError and crashes the caller\n#: (uncontrolled recursion, CWE-674); past this depth a normal\n#: LogicalExpressionException is raised instead. Configurable.\nMAX_PARSE_DEPTH = 200\n```\n(`nltk/sem/logic.py:102-107`), and `nltk/jsontags.py`\u0027s `JSONTaggedDecoder` similarly has `MAX_DECODE_DEPTH = 200` with an explicit depth check. `nltk/featstruct.py` has no analogous protection.\n\n`FeatureGrammar.fromstring()` (`nltk/grammar.py`) parses feature structures embedded in FCFG grammar rules via the same `FeatStructReader`, so the same crash is reachable through grammar-string parsing as well as through `FeatStruct()` directly.\n\n### PoC\n\nVerified against the current `develop` branch in a clean virtualenv (Python 3.12, NLTK installed from this checkout via `pip install -e .`):\n\n```python\nfrom nltk.featstruct import FeatStruct\n\ndepth = 167\npayload = \"[a=\" * depth + \"1\" + \"]\" * depth   # 669 bytes\nFeatStruct(payload)\n```\n\nResult:\n```\nTraceback (most recent call last):\n  ...\n  File \".../nltk/featstruct.py\", line 2310, in _read_partial_featdict\n    value, position = self._read_value(name, s, position, reentrances)\n  File \".../nltk/featstruct.py\", line 2440, in _read_value\n    return self.read_value(s, position, reentrances)\n  File \".../nltk/featstruct.py\", line 2446, in read_value\n    return handler_func(s, position, reentrances, match)\n  [... repeats ~167 times ...]\nRecursionError: maximum recursion depth exceeded\n```\n\n- Crash threshold: nesting depth 167 (binary-searched between 50 and 200).\n- Payload size: 669 bytes \u2014 fits trivially in a single HTTP request body/query parameter.\n- Time to crash: \u003c2ms \u2014 no resource exhaustion is needed, only recursion depth.\n\nMinimal reproduction (no server required):\n```bash\npython3 -c \"\nfrom nltk.featstruct import FeatStruct\nFeatStruct(\u0027[a=\u0027 * 200 + \u00271\u0027 + \u0027]\u0027 * 200)\n\"\n```\n\nIllustrative server-side context (not part of NLTK itself, but representative of how the bug becomes reachable):\n```python\nfrom flask import Flask, request\nfrom nltk.featstruct import FeatStruct\n\napp = Flask(__name__)\n\n@app.route(\"/parse\", methods=[\"POST\"])\ndef parse_grammar():\n    return {\"result\": str(FeatStruct(request.json[\"grammar\"]))}\n```\nA POST of `{\"grammar\": \"[a=\" * 200 + \"1\" + \"]\" * 200}` to this endpoint raises the uncaught `RecursionError` inside the request handler.\n\n### Impact\n\n**Vulnerability type:** Denial of Service via uncontrolled recursion (CWE-674). This is not a memory-corruption bug and does not lead to code execution or data disclosure \u2014 Python\u0027s own recursion-limit safety net converts what would be a C-level stack overflow into a catchable (but here, uncaught) `RecursionError`.\n\n**Who is affected:** Any application that passes externally-supplied text into `nltk.featstruct.FeatStruct()` or `nltk.grammar.FeatureGrammar.fromstring()` \u2014 for example, NLP/computational-linguistics teaching tools, unification-grammar demo services, or NLU pipelines that accept user-authored feature grammars. This is a narrower slice of NLTK\u0027s user base than, e.g., tokenization or POS tagging, since feature-structure/unification-grammar parsing is a more specialized part of the library.\n\n**Practical severity depends on deployment:**\n- In typical WSGI-style web frameworks (Flask/Django/FastAPI behind gunicorn/uwsgi), an uncaught exception inside a request handler is caught at the framework/server boundary: the single request fails (HTTP 500), the worker process itself survives, and unaffected requests are unimpacted.\n- In single-threaded or per-task-unprotected contexts (e.g. a queue-consuming worker without per-task exception isolation), the uncaught `RecursionError` can terminate the entire process; without a process supervisor that auto-restarts it, this is a persistent outage until manually restarted. An attacker who repeats the payload can keep such a worker in a crash loop for as long as the attack continues.\n\n**Suggested fix:** Add a depth counter and a `MAX_PARSE_DEPTH`-style constant to `FeatStructReader`, mirroring the existing fix in `nltk/sem/logic.py`, and raise the library\u0027s normal `ValueError`-based parse error once the limit is exceeded instead of letting `RecursionError` propagate.",
  "id": "GHSA-cw6x-m8jw-qmrh",
  "modified": "2026-09-02T14:33:22Z",
  "published": "2026-09-02T14:33:22Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/nltk/nltk/security/advisories/GHSA-cw6x-m8jw-qmrh"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-81724"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nltk/nltk/commit/43c7b78cc8ea37e5cd3a129e27e32c415ea21cf1"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/nltk/nltk"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nltk/nltk/releases/tag/v3.10.3"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/nltk/PYSEC-2026-3739.yaml"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/nltk-before-3.10.3-denial-of-service-via-uncontrolled-recursion"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "NLTK: Uncontrolled recursion in nltk.featstruct.FeatStructReader causes unhandled RecursionError (DoS) via deeply nested feature-structure input"
}

{
  "affected": [],
  "aliases": [
    "CVE-2018-9138"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-674"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2018-03-30T08:29:00Z",
    "severity": "MODERATE"
  },
  "details": "An issue was discovered in cplus-dem.c in GNU libiberty, as distributed in GNU Binutils 2.29 and 2.30. Stack Exhaustion occurs in the C++ demangling functions provided by libiberty, and there are recursive stack frames: demangle_nested_args, demangle_args, do_arg, and do_type.",
  "id": "GHSA-cwff-w289-23wm",
  "modified": "2022-05-13T01:27:12Z",
  "published": "2022-05-13T01:27:12Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2018-9138"
    },
    {
      "type": "WEB",
      "url": "https://sourceware.org/bugzilla/show_bug.cgi?id=23008"
    },
    {
      "type": "WEB",
      "url": "https://usn.ubuntu.com/4326-1"
    },
    {
      "type": "WEB",
      "url": "https://usn.ubuntu.com/4336-1"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

{
  "affected": [],
  "aliases": [
    "CVE-2020-23804"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-674"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-08-22T19:16:19Z",
    "severity": "HIGH"
  },
  "details": "Uncontrolled Recursion in pdfinfo, and pdftops in poppler 0.89.0 allows remote attackers to cause a denial of service via crafted input.",
  "id": "GHSA-cwfg-vhjr-jvv6",
  "modified": "2023-12-08T21:30:29Z",
  "published": "2023-08-22T21:30:25Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-23804"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.freedesktop.org/poppler/poppler/-/issues/936"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2023/10/msg00022.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}