Malicious PDF — malware analysis report

Static analysis result for SHA-256 23b8de6427c7ced9…

MALICIOUS

PDF

84.9 KB Created: 2021-03-27 20:55:30 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-30
MD5: 7de4f3668cb0ba12add60de6773fe409 SHA-1: 9376707ef89638f37d63c83ee92ae5ec9b6e9757 SHA-256: 23b8de6427c7ced9be9e281c1494f10b16b43df4cfa4bd0887b91e6990249477
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged by multiple heuristics as a link farm, containing numerous external URLs. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or SEO spam. While no scripts were explicitly extracted, the PDF structure itself facilitates the redirection to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://golowaki.ru/award?keyword=time+and+work+shortcut+formula+pdf PDF link annotation
    • http://ryursew.space/good_weight_lifting_routine_for_beginnersgt6tn.pdfIn PDF document text
    • http://sushibara.net/20039147292kxj75.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365567/normal_601a08df3020b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424364/normal_603802aa4fa50.pdfIn PDF document text
    • http://futup.ru/modern_family_season_2_scriptndcds.pdfIn PDF document text
    • http://clubstore.pro/donezedaperokuzuromiwaretss3ay.pdfIn PDF document text
    • http://winwites.space/absolute_monarchy_activity_worksheetu4qbq.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476140/normal_605d7bbd19527.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/158fdd93-498d-41ea-ab3b-b71f4e03a000/plantronics_voyager_legend_pc_software.pdfIn PDF document text
    • https://ca6b24e6-01cd-4368-a310-1df05077a315.filesusr.com/ugd/11b39a_9bf1899513cf466a81cdc47da77c74d6.pdf?index=trueIn PDF document text
    • https://a867a740-3546-49c9-bb92-c76f735cad7e.filesusr.com/ugd/c312ff_d043f2ab22804fb6b73c6a5983acea1d.pdf?index=trueIn PDF document text
    • https://3f740848-0e57-4b51-8596-564812021bec.filesusr.com/ugd/cbe17c_dffcbadefdd74f768f1c0b9ebc19b301.pdf?index=trueIn PDF document text
    • https://b962d5b8-8819-42e3-9ba3-d95e8366760e.filesusr.com/ugd/f51585_d4b4d3e08fa044b095bc269637bf5e19.pdf?index=trueIn PDF document text
    • https://05e27880-d5e1-4d3d-8428-ba943e9300bc.filesusr.com/ugd/b56239_f507a6bf2f5e4f889798aa2f3d4c5a22.pdf?index=trueIn PDF document text
    • https://a97be2a3-bfb5-42de-bba9-b145341b31aa.filesusr.com/ugd/1f2860_baef2ecc12da46b6a96abcdce8ee57f2.pdf?index=trueIn PDF document text
    • https://ca39a19f-16f9-469f-ab0b-65ec0463b8d0.filesusr.com/ugd/cc9b97_c63352e92efd46ccbf66e7635e5bdd76.pdf?index=trueIn PDF document text
    • https://b86313a8-447b-404d-ae6d-bc69740d899e.filesusr.com/ugd/e54fc7_5d84cf33b0194251a4843740f070ddcf.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c6bff83f-84c2-426c-a609-46d615150e14/70197280906.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fe3368bb-a149-4206-9173-60a9e29b3f87/23862472363.pdfIn PDF document text
    • https://709e7e89-b264-4d73-b757-064736ed86f1.filesusr.com/ugd/f523c3_647a2dcfdee348158e2a1b623992c9bc.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1c02d5a8-05c9-47d0-9010-50d2b91464c2/ladofonatitofo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/44d8cf25-a26a-4f61-a25b-7af2678e9802/halal_food_in_honolulu_hawaii.pdfIn PDF document text
    • https://78fa80b2-8629-447b-ad63-53e91e8d4948.filesusr.com/ugd/8f02de_c9dcef7fbf4844f58b33022a6136d851.pdf?index=trueIn PDF document text
    • https://2a4065d7-883d-43e8-a524-7ce9aa4b4e88.filesusr.com/ugd/ccb1c6_973769ae72c245fa94ae80e19842b1b1.pdf?index=trueIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010ac7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AC7 5500 bytes
SHA-256: cdd1354143f760b72c6ac4498d0a45fbf6146ea50461a23ed2a85609df997e72
font_01_sfnt_off00011d68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D68 11860 bytes
SHA-256: c3e4cafa8dac049f08747fb114ae973a9ac6e8e7b58a779a35e6ab88a019d075