Malicious PDF — malware analysis report

Static analysis result for SHA-256 e639e736f4869cf8…

MALICIOUS

PDF

92.0 KB Created: 2021-09-11 14:26:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 031d32f861d1bf4287b9dfebcdc95ca8 SHA-1: d657e5c8f6d0d3e19c86e57fe87732c279bacce9 SHA-256: e639e736f4869cf849cb85eb679d6b25882caf458d62989c2412e93d0bbbcd2b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised websites or disposable hosting, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery, likely via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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
  • 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://smidgel.ru/uplcv?utm_term=interstellar+full+movie+free PDF link annotation
    • http://szolnokepul.hu/userfiles/file/jiresabo.pdfIn PDF document text
    • https://autosaloncenter.com/uploads/files/29072514574.pdfIn PDF document text
    • http://bcslaw.hu/admin/fck_upload/file/mekobefofedivojafabo.pdfIn PDF document text
    • http://www.afurg.com.br/assets/ckfinder/userfiles/files/95623161580.pdfIn PDF document text
    • http://xn--80aantfcaehjbxzf1m.xn--p1ai/userfiles/file/fubazisawizesasel.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613a913165e20---63810435811.pdfIn PDF document text
    • http://dolonchem.com/upload/files/napegibomimopom.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/11d9e46bc86c4dbaff9e0ea531758c62/pakeluwe.pdfIn PDF document text
    • http://mamolenasnc.it/userfiles/files/digotuwilekibawuruk.pdfIn PDF document text
    • http://woodlander.sk/grafika/file/fegaligi.pdfIn PDF document text
    • https://globalcircle.club/userfiles/file/62566237612.pdfIn PDF document text
    • https://petribax.com/userfiles/file/bosifuvesazujulegumameris.pdfIn PDF document text
    • http://kxqcgs.com/filespath/files/20210906071955.pdfIn PDF document text
    • https://australiancaravancentre.com.au/application/third_party/ckfinder/userfiles/files/gulidujutakozodexamuliz.pdfIn PDF document text
    • https://wanna-drive.nl/files/File/59339568314.pdfIn PDF document text
    • https://nhanloc.net/userfiles/file/wadewowutifefinolivip.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/161354181c5460---pevedavimofujetemu.pdfIn PDF document text
    • http://ipmarketing.net/FCKeditor/editor/filemanager/connectors/userfiles/file/japakekosox.pdfIn PDF document text
    • http://srub-servis.ru/userfiles/file/ladizida.pdfIn PDF document text
    • http://aristosaigonhotel.com/uploads/files/13860056718.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/0e9158e1be663c28ef896e332f6d5aa7/6672888718.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613a879f9f369---dasotomivinozamiraji.pdfIn PDF document text
    • https://viettrungson.com/media/Files/23603392491.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://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_off00010629.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10629 17228 bytes
SHA-256: 45f0ea28706aa2a3c5369515a665ddb2c810e0b377b21aaabe04f185f672696e
font_01_sfnt_off000132cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132CB 10492 bytes
SHA-256: 87be7482b0c25cfb2b25f9902dd8cef95544d3fb0d577028cc35ac794bef0117
font_02_sfnt_off00014aae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14AAE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1