Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7caa2d17e772b2d…

MALICIOUS

PDF

75.1 KB Created: 2021-09-10 03:35:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: d6cb55e227c4ce797ca2c84c01e29ab4 SHA-1: 89e5b1596faf1774ac4162b7a193eff0b5c00b51 SHA-256: a7caa2d17e772b2d59354c926b2606caeb4f861cc48c01b94d3f333b6acaa48e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to potentially compromised or disposable hosting domains. The primary purpose appears to be directing users to external, untrusted resources, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://kemxoithanhhang.vn/app/webroot/files/images/pages/files/9504575654.pdf In PDF document text
    • https://globalybm.com/ckfinder/userfiles/files/1630749723.pdfIn PDF document text
    • http://f-kcc.jp/user_data/userfiles/files/vofivodatunegiwupuxef.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/f4f0ca0a6f92f6612e3a355a803b2f8b/ninabadibepiliziwudote.pdfIn PDF document text
    • http://portakalweb.net/home/portakal/public_html/ckfinder/userfiles/files/29122948295.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1612f365bc1489---12639305791.pdfIn PDF document text
    • http://gillsandgeckos.com/userfiles/file/dagizelijezitakoxe.pdfIn PDF document text
    • http://finalbrand.cz/upload/file/nowigebamopetuwarega.pdfIn PDF document text
    • http://garderoba.sk/images/_file/kuxigep.pdfIn PDF document text
    • http://keitbg.com/images/files/35938282873.pdfIn PDF document text
    • http://muszempilla.com/files/file/66152343894.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/056799126c60713cdba3f9afdaab12d7/80334262385.pdfIn PDF document text
    • http://kondicionery-pushkino.ru/upload_picture/file/83272649480.pdfIn PDF document text
    • http://bocghebinhduong.com/media/ftp/file/1391082570.pdfIn PDF document text
    • http://maynenkhipuma.vn/quangbasanpham/app/webroot/upload/image/files/42764396080.pdfIn PDF document text
    • http://ccspatti.org/userfiles/file/74510784729.pdfIn PDF document text
    • https://sofupingame.com/calisma2/files/uploads/baterimotowalolawomuv.pdfIn PDF document text
    • https://thefertilizergranulator.com/d/files/bowijusimen.pdfIn PDF document text
    • http://orem.mn/uploads/files/65676753737.pdfIn PDF document text
    • https://adikketiga.com/contents/files/91693873649.pdfIn PDF document text
    • http://strojsteel.cz/webpagebuilder/ckfinder/userfiles/files/gujerasojusaka.pdfIn PDF document text
    • http://keyflounge.nl/userfiles/file/50362878009.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=i+fine+thank+you+love+you+hdPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c05c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC05C 18128 bytes
SHA-256: a36552b39a9a45877eefcb9243dfcd95f8050097e91b9bbc9fadf57e57510307
font_01_sfnt_off0000ef86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF86 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001079d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1079D 10504 bytes
SHA-256: b3ef5ecddb5697d59ae0efc73398cf1975f716509ee1ba68af6ee33bf6ad02f0