Malicious PDF — malware analysis report

Static analysis result for SHA-256 437980b35abbd3c9…

MALICIOUS

PDF

78.2 KB Created: 2021-09-05 05:59:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: de174b3b95345b307937bd05bd3d056f SHA-1: 53fe2d84c192171fc780520ac43d8a3065acef3f SHA-256: 437980b35abbd3c92834443401358ac2623f80bf31d08b10bf91e521aff729dd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, forming a link farm. These links likely serve to redirect users to phishing pages or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://crewmak.ru/uplcv?utm_term=marmita+chic+e+saud%C3%A1vel+pdf PDF link annotation
    • https://ewastexperts.com/userfiles/files/83284016948.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606ebbb88074d---vixiti.pdfIn PDF document text
    • https://msvadba.ru/files/file/516189814.pdfIn PDF document text
    • http://diversecityuk.com/userfiles/file/39243493309.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160b03e971cc34---tolopiravefokuvomer.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/25827620683.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/160f0827f538d4---bisewesubafejagofaguj.pdfIn PDF document text
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/8170d33d194a0afaa28f25756fefeed7/namulakoxaxopere.pdfIn PDF document text
    • https://sitycare.com/FCK-UserFiles/files/68438069610.pdfIn PDF document text
    • http://au-coeur-du-temps.com/userfiles/file/56409736536.pdfIn PDF document text
    • https://topupdana.com/contents//files/kavibusinitalorotematuv.pdfIn PDF document text
    • http://nissanotogovap.vn/uploads/images/files/xanosutot.pdfIn PDF document text
    • http://abc-tel.ru/data/File/fosobuvewo.pdfIn PDF document text
    • http://ebsenglish.net/_UploadFile/Images/file/28571953276.pdfIn PDF document text
    • http://bischofs-scheune.de/userfiles/file/38025778674.pdfIn PDF document text
    • http://www.tiande-global.com/ckfinder/userfiles/files/33154134866.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16116b357dbfb3---zererosetuwav.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160743e6c564f7---57748036046.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/0ad1510d9c7718f7a36f23dd9bdb29f6/sekegivubub.pdfIn PDF document text
    • https://supermagnum-bg.com/userfiles/file/35427770819.pdfIn PDF document text
    • https://lajovisena.com/gallery/file/zuwokakunorudinonatevaxi.pdfIn PDF document text
    • http://npi-management.org/ressource/site-image/files/70639594636.pdfIn PDF document text
    • http://ngor2-3.com/file_media/file_image/file/68605305290.pdfIn PDF document text
    • https://guapa2.com/admin/fck/file/32180042619.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_off0000c9ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9BA 18604 bytes
SHA-256: d7d4c39d4d589672baac63436297129fea9ba493c04e6882a60f0a2f5c95337b
font_01_sfnt_off0000f85b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF85B 11000 bytes
SHA-256: 723e1c1217b67f23d6d013053d2f35d29505b0a8dfe3c51561f0928aea4b0e11
font_02_sfnt_off0001118d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1118D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1