Vulnerability-Lookup

GHSA-Q683-6FHR-JVG2

Vulnerability from github – Published: 2026-11-10 18:31 – Updated: 2026-11-10 18:31

Details

Improper Handling of Highly Compressed Data (CWE-409) in the ZIP loader of whatstk from 0.7.0 before 0.9.0 allows a party that supplies a chat export to exhaust the memory and the disk of the process that parses it, because _str_from_file() (whatstk/whatsapp/parser.py) calls zip_ref.extractall() with no bound on the size of the members and no check of the compression ratio, then reads the extracted file in full with f.read(). The only guard on the archive counts the extracted files and raises when there is not exactly one, but it runs after extractall() has already written them, so it does not prevent the cost. _clean_text() then passes the whole text through unicodedata.normalize("NFKD", text), which holds a second copy, and the parse builds a list of regular expression matches and a DataFrame over it, so peak memory is a multiple of the decompressed text rather than of the archive. A ZIP is a documented input of WhatsAppChat.from_source() and df_from_whatsapp(), and is the form in which WhatsApp exports a chat on iOS, so the attacker supplies the whole file. This results in a small upload costing hundreds of megabytes of memory and of disk, and in the process being killed where that exceeds what is available.

Severity

6.7 (Medium)


                  
                    CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

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{
  "affected": [],
  "aliases": [
    "CVE-2026-121691"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-409"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-11-10T18:17:20Z",
    "severity": "MODERATE"
  },
  "details": "Improper Handling of Highly Compressed Data (CWE-409) in the ZIP loader of whatstk from 0.7.0 before 0.9.0 allows a party that supplies a chat export to exhaust the memory and the disk of the process that parses it, because _str_from_file() (whatstk/whatsapp/parser.py) calls zip_ref.extractall() with no bound on the size of the members and no check of the compression ratio, then reads the extracted file in full with f.read(). The only guard on the archive counts the extracted files and raises when there is not exactly one, but it runs after extractall() has already written them, so it does not prevent the cost. _clean_text() then passes the whole text through unicodedata.normalize(\"NFKD\", text), which holds a second copy, and the parse builds a list of regular expression matches and a DataFrame over it, so peak memory is a multiple of the decompressed text rather than of the archive. A ZIP is a documented input of WhatsAppChat.from_source() and df_from_whatsapp(), and is the form in which WhatsApp exports a chat on iOS, so the attacker supplies the whole file. This results in a small upload costing hundreds of megabytes of memory and of disk, and in the process being killed where that exceeds what is available.",
  "id": "GHSA-q683-6fhr-jvg2",
  "modified": "2026-11-10T18:31:49Z",
  "published": "2026-11-10T18:31:49Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-121691"
    },
    {
      "type": "WEB",
      "url": "https://github.com/lucasrodes/whatstk/pull/182"
    },
    {
      "type": "WEB",
      "url": "https://github.com/lucasrodes/whatstk/commit/01d66d8"
    },
    {
      "type": "WEB",
      "url": "https://github.com/lucasrodes/whatstk/releases/tag/v0.9.0"
    },
    {
      "type": "WEB",
      "url": "https://secur0.com/en/cna/cve-list/cve-2026-121691-whatstk-zip-decompression-bomb"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/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"
    }
  ]
}

CVE-2026-121691 (GCVE-0-2026-121691)

Vulnerability from cvelistv5 – Published: 2026-11-10 17:29 – Updated: 2026-11-10 17:29 X_Open Source

Title

Unbounded decompression in the whatstk ZIP loader exhausts memory and disk

Summary

Severity

6.7 (Medium)


                        
                          CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CWE

CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)

Assigner

Secur0 CNA under the INCIBE root

CNA scorecard A 99/100 over 47 records in the last 180 days details

References

4 references

URL	Tags
https://github.com/lucasrodes/whatstk/pull/182	patch
https://github.com/lucasrodes/whatstk/commit/01d66d8	patch
https://github.com/lucasrodes/whatstk/releases/ta…	release-notes
https://secur0.com/en/cna/cve-list/cve-2026-12169…	third-party-advisorytechnical-description

Impacted products

1 product

Vendor	Product	Version
lucasrodes	whatstk	Affected: 0.7.0 , < 0.9.0 (semver) cpe:2.3:a:lucasrodes:whatstk::::::python::*

Credits

Jorge Rey Cotallo (reddev) Xoán M. Otero Jorge Darío Rivas Secur0 CNA Lucas Rodés-Guirao

Show details on NVD website

JSON

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "collectionURL": "https://pypi.org",
          "defaultStatus": "unaffected",
          "packageName": "whatstk",
          "product": "whatstk",
          "programFiles": [
            "whatstk/whatsapp/parser.py"
          ],
          "repo": "https://github.com/lucasrodes/whatstk",
          "vendor": "lucasrodes",
          "versions": [
            {
              "lessThan": "0.9.0",
              "status": "affected",
              "version": "0.7.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:lucasrodes:whatstk:*:*:*:*:*:python:*:*",
                  "versionEndExcluding": "0.9.0",
                  "versionStartIncluding": "0.7.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ],
          "operator": "OR"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Jorge Rey Cotallo (reddev)"
        },
        {
          "lang": "en",
          "type": "analyst",
          "value": "Xo\u00e1n M. Otero Jorge"
        },
        {
          "lang": "en",
          "type": "analyst",
          "value": "Dar\u00edo Rivas"
        },
        {
          "lang": "en",
          "type": "coordinator",
          "value": "Secur0 CNA"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "Lucas Rod\u00e9s-Guirao"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "Improper Handling of Highly Compressed Data (CWE-409) in the ZIP loader of whatstk from 0.7.0 before 0.9.0 allows a party that supplies a chat export to exhaust the memory and the disk of the process that parses it, because \u003ccode\u003e_str_from_file()\u003c/code\u003e (\u003ccode\u003ewhatstk/whatsapp/parser.py\u003c/code\u003e) calls \u003ccode\u003ezip_ref.extractall()\u003c/code\u003e with no bound on the size of the members and no check of the compression ratio, then reads the extracted file in full with \u003ccode\u003ef.read()\u003c/code\u003e. The only guard on the archive counts the extracted files and raises when there is not exactly one, but it runs after \u003ccode\u003eextractall()\u003c/code\u003e has already written them, so it does not prevent the cost. \u003ccode\u003e_clean_text()\u003c/code\u003e then passes the whole text through \u003ccode\u003eunicodedata.normalize(\"NFKD\", text)\u003c/code\u003e, which holds a second copy, and the parse builds a list of regular expression matches and a DataFrame over it, so peak memory is a multiple of the decompressed text rather than of the archive. A ZIP is a documented input of \u003ccode\u003eWhatsAppChat.from_source()\u003c/code\u003e and \u003ccode\u003edf_from_whatsapp()\u003c/code\u003e, and is the form in which WhatsApp exports a chat on iOS, so the attacker supplies the whole file. This results in a small upload costing hundreds of megabytes of memory and of disk, and in the process being killed where that exceeds what is available."
            }
          ],
          "value": "Improper Handling of Highly Compressed Data (CWE-409) in the ZIP loader of whatstk from 0.7.0 before 0.9.0 allows a party that supplies a chat export to exhaust the memory and the disk of the process that parses it, because _str_from_file() (whatstk/whatsapp/parser.py) calls zip_ref.extractall() with no bound on the size of the members and no check of the compression ratio, then reads the extracted file in full with f.read(). The only guard on the archive counts the extracted files and raises when there is not exactly one, but it runs after extractall() has already written them, so it does not prevent the cost. _clean_text() then passes the whole text through unicodedata.normalize(\"NFKD\", text), which holds a second copy, and the parse builds a list of regular expression matches and a DataFrame over it, so peak memory is a multiple of the decompressed text rather than of the archive. A ZIP is a documented input of WhatsAppChat.from_source() and df_from_whatsapp(), and is the form in which WhatsApp exports a chat on iOS, so the attacker supplies the whole file. This results in a small upload costing hundreds of megabytes of memory and of disk, and in the process being killed where that exceeds what is available."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "LOCAL",
            "baseScore": 6.7,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "ACTIVE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-409",
              "description": "CWE-409 Improper Handling of Highly Compressed Data (Data Amplification)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-11-10T17:29:34.562Z",
        "orgId": "4daa8cea-433a-44bd-9456-53b127fc289a",
        "shortName": "Secur0"
      },
      "references": [
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/lucasrodes/whatstk/pull/182"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/lucasrodes/whatstk/commit/01d66d8"
        },
        {
          "tags": [
            "release-notes"
          ],
          "url": "https://github.com/lucasrodes/whatstk/releases/tag/v0.9.0"
        },
        {
          "tags": [
            "third-party-advisory",
            "technical-description"
          ],
          "url": "https://secur0.com/en/cna/cve-list/cve-2026-121691-whatstk-zip-decompression-bomb"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "Upgrade to whatstk 0.9.0 or later, which rejects a source larger than 50 MB by default and accepts a \u003ccode\u003emax_size\u003c/code\u003e argument to lower that bound."
            }
          ],
          "value": "Upgrade to whatstk 0.9.0 or later, which rejects a source larger than 50 MB by default and accepts a max_size argument to lower that bound."
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "tags": [
        "x_open-source"
      ],
      "title": "Unbounded decompression in the whatstk ZIP loader exhausts memory and disk",
      "x_generator": {
        "engine": "Vulnogram 1.0.5"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "4daa8cea-433a-44bd-9456-53b127fc289a",
    "assignerShortName": "Secur0",
    "cveId": "CVE-2026-121691",
    "datePublished": "2026-11-10T17:29:34.562Z",
    "dateReserved": "2026-11-03T20:07:54.134Z",
    "dateUpdated": "2026-11-10T17:29:34.562Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

Order JSON

How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Publication & reservation Sightings KEV catalogs Other timestamps

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

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