Malicious PDF — malware analysis report

Static analysis result for SHA-256 7d5efa85ddb5f647…

MALICIOUS

PDF

76.8 KB Created: 2021-06-10 09:20:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: d8f3e6f86160e9d6975d49b71a27b565 SHA-1: 3f34701cf8427b09af50f26fa6de107f52b11e92 SHA-256: 7d5efa85ddb5f647014f61f26abf31d1ca1b3efadc51123acb56161bfb76a0d8
146 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with a significant number pointing to disposable or potentially malicious hosting, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic and the ML_NYX_PDF_MALICIOUS flag. ClamAV also detected it as Pdf.Phishing.Trojan. The presence of UTM parameters and the overall structure suggest a phishing or spam campaign aiming to redirect users to external sites. No scripts were extracted, but the PDF structure itself is indicative of malicious intent.

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 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://krisoc.ru/pbw?utm_term=copy+amiibo+android PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4421461/normal_60109017970d1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465938/normal_6023daee4c38f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501509/normal_6017b27312b58.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4417405/normal_6001d8439e0bd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486350/normal_60beb78839283.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391013/normal_606b6311ef61f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417214/normal_6033c7e8ea7f0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4368745/normal_5fe283e3c1eb4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4408197/normal_5fed8f00eddb8.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4382627/normal_60b24dd3e168f.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://tufukamapaf.pbworks.com/f/plate_girder_bridge_design_example.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b967862f-63d1-47d2-9bea-88a728975372/78610462790.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/11146711-bd21-462c-96b8-9d26d58c5ecf/gaxonevugaburomewikuru.pdfIn PDF document text
    • http://pizuwamamevu.pbworks.com/f/boom_beach_hack.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/85421aed-f7c3-42cf-8568-2f52326ab097/27638912717.pdfIn PDF document text
    • http://sorawako.pbworks.com/w/file/fetch/144613464/among_us_hack_mod_menu_pc_always_imposter_android.pdfIn PDF document text
    • http://vemebana.pbworks.com/f/sims_4_free_download_with_all_expansion_packs.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/08c297a7-7270-41f5-a433-fa953b917a35/75835051598.pdfIn PDF document text
    • http://sipibujewadu.pbworks.com/f/example_of_ethnographic_research_paper.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8f90708a-2bfb-44f8-991c-3c870914a0b6/iso_pid_pump_symbols.pdfIn PDF document text
    • http://gosirata.pbworks.com/w/file/fetch/144456453/how_many_sodium_atoms_does_cuso4_have.pdfIn PDF document text
    • http://vesusezipuwe.pbworks.com/f/24136216926.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/60eb94d8-b9d6-447c-8bc9-6a83414fb067/21590074559.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9a284a0b-24ae-4775-816f-87977713c0e2/what_are_some_examples_of_fairy_tales.pdfIn 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_off0000ef1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF1A 5044 bytes
SHA-256: 247c6821dd57cfefc978822f29af2eaf40c54535d48091708ec00565f5c9a3fc
font_01_sfnt_off00010026.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10026 11044 bytes
SHA-256: 6e955ba1493afced651f23af7fdb5f9ab3a107b2a0490f4fbbfd953218cd2169