Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc36e4af62f33932…

MALICIOUS

PDF

80.8 KB Created: 2021-09-09 09:48:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 52d5917f202e772d63b9c675e8647b76 SHA-1: a2c1e27e4044752ee28318f67fba0e25cc440659 SHA-256: fc36e4af62f33932d7282b71d4b69faaf7616a69c33ca87662adf21297165f27
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by a machine learning classifier and ClamAV as malicious. It contains numerous embedded URLs, many of which point to PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for these links, which is common in phishing and malware distribution campaigns. While no scripts were explicitly extracted, the nature of the embedded URLs and the heuristics suggest an intent to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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 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://doina.md/fckeditorfiles/file/nufazoxopu.pdf In PDF document text
    • https://jpt.mysmartedu.com/uploadimages/files/gorexujixunaxurukivuvu.pdfIn PDF document text
    • https://denimder.org/resimler/files/dusikoxujagomatefu.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/wuxisopakutixobasoro.pdfIn PDF document text
    • https://apz-arte.com/ckfinder/userfiles/files/pivemotax.pdfIn PDF document text
    • https://gestionarival.com/userfiles/file/26581857300.pdfIn PDF document text
    • https://electrodomesticaruano.com/images/ckfinder/files/binolofezelofubo.pdfIn PDF document text
    • http://immodraft.nrw/images/architekten_agentur_images_/file/nelina.pdfIn PDF document text
    • http://bobas24.pl/Upload/file/10031734588.pdfIn PDF document text
    • https://rugerwafers.com/demo/ruger/beta/userfiles/files/31862580240.pdfIn PDF document text
    • http://vnationwide.com/userfiles/files/zeruvuxapadiwuwebexani.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/19da33d27e025a1921e378f6b9e8581c/mufafetigaxizexikejepok.pdfIn PDF document text
    • https://ilonew.tasksplan.com/userfiles/files/97602935130.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1612f96aca4eb5---55570809638.pdfIn PDF document text
    • https://hyosungulf.com/uploads/file/78682548591.pdfIn PDF document text
    • http://severstroysnab.ru/userfiles/file/44542876861.pdfIn PDF document text
    • http://majorpropertygroup.com/userfiles/files/jogiwevanamebaterekugi.pdfIn PDF document text
    • http://jikaramen.com/uploads/files/kogegozapegimelomevesejis.pdfIn PDF document text
    • http://angel-conference.org/upload_fck/file/2021-9-6/20210906061258966586.pdfIn PDF document text
    • http://offerseir.com/basefile/offerseircom/files/ponobajidonapefemidid.pdfIn PDF document text
    • http://k12kos.com/ckfinder/userfiles/files/77284352366.pdfIn PDF document text
    • https://cissud.eu/uploads/ck_editor/files/94924401824.pdfIn PDF document text
    • https://alebusph.centralcms.cloud/galeria/files/1989019210.pdfIn PDF document text
    • https://alshuka.ps/ckfinder/userfiles/files/4561806030.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=original+voice+changer+male+to+femalePDF 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_off0000d7d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7D5 17344 bytes
SHA-256: d5329f3c69171e1597a4de1c28917ef86c92b1fdca66e28256e38654c5f93bfb
font_01_sfnt_off00010501.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10501 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D18 10704 bytes
SHA-256: 93c34489095785c4bc38400762d68794af67c6516bab3b658ee296ddddb6ec87