Malicious PDF — malware analysis report

Static analysis result for SHA-256 9545b660c071dadd…

MALICIOUS

PDF

81.7 KB Created: 2021-03-18 17:04:30 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 97511f57ddda93e7af03079df3356281 SHA-1: 40903c448c7397b689b17bd63dcbbd252b644014 SHA-256: 9545b660c071daddf8b3909facf69eb81a399f5fe2514a218b962706d53f1e27
186 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or SEO manipulation tactic. The primary malicious URL identified is https://zajinet.ru/award?keyword=fetal+development+pictures+pdf, which is likely used to redirect users to further malicious content or phishing pages. No scripts were extracted, but the PDF structure itself is used to facilitate the malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://zajinet.ru/award?keyword=fetal+development+pictures+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4501193/normal_603a53f27dd1f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4462059/normal_6004093345e36.pdfIn PDF document text
    • https://cdn.sqhk.co/bewewojiwo/cjahg7I/winewuralapinerelo.pdfIn PDF document text
    • http://reabook.online/jurumakajokuxugasekesulob9tumx.pdfIn PDF document text
    • https://cdn.sqhk.co/jefapukawore/b0MjgSd/shadow_skate_mod_apk_android_1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385859/normal_5fe903d394ba4.pdfIn PDF document text
    • http://firstflirts.site/bob_stroller_accessories_travel_bag7u2zx.pdfIn PDF document text
    • http://tublitalia.fun/how_much_does_a_software_tester_earn_in_australia8tjhe.pdfIn PDF document text
    • https://cdn.sqhk.co/fekigimuzib/gfohc1w/dazofaranevuwuzo.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/07e457cb-fe9d-4b16-8d1c-423a40451f82/down_the_rabbit_hole_book_peter_abrahams.pdfIn PDF document text
    • https://s3.amazonaws.com/godoremitiwuja/58287494286.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8c0465a3-d88c-4bad-adb8-04c2d0870f6a/12835109906.pdfIn PDF document text
    • https://a4edf7fa-b057-49b5-8014-e5fd436fbef3.filesusr.com/ugd/c8b2c5_ffcbd6fae0e04b11a3c43a9160be974b.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/poresi/6690365908.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/abbeaf06-c8c3-4e0f-b3fb-9333abed4634/samsung_tv_turns_on_but_has_no_picture.pdfIn PDF document text
    • https://651f5d5e-5f42-4fb0-8380-889764ca350f.filesusr.com/ugd/b2f7c1_9885ff3eef494a11ad28490927544f91.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/bulikowexunepov/atm_card_use_video.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/26ced598-c551-459a-9181-671180e35a9b/46547851751.pdfIn PDF document text
    • https://s3.amazonaws.com/gumegulaxi/coursera_r_programming_week_2_assignment_answers.pdfIn PDF document text
    • https://s3.amazonaws.com/baposivarabuj/bisakenejil.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f6df0a96-ab2a-454b-85db-17b5da74ecbc/42309340802.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_off00010042.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10042 5316 bytes
SHA-256: be00c9328c20a44c8d938df35bdf526fc8e5b61c02c505cb192e267986a511c8
font_01_sfnt_off0001124e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1124E 11892 bytes
SHA-256: 4293d677692c059042792f041fd658e4fb861627e7fcda910fa332fa1b775806