Malicious PDF — malware analysis report

Static analysis result for SHA-256 c0f83ac8ddbfa496…

MALICIOUS

PDF

70.6 KB Created: 2021-09-22 09:56:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4649f7d86eaed012d6bf14a40104f3c9 SHA-1: 26912422e1d9c6c98c84479e87a14772cc9eea22 SHA-256: c0f83ac8ddbfa496692598dc2066ec81d7ad50bc826c380083ed13b691455792
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or malware distribution attempt. It contains numerous links, many hosted on disposable domains or compromised WordPress sites, suggesting it functions as a link farm to direct users to malicious content. The presence of embedded URLs and the nature of the heuristics strongly suggest an attempt to exploit users by directing them to external, untrusted resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://irlanc.ru/uplcv?utm_term=how+to+put+conference+call+in+android+mobile PDF link annotation
    • http://magendans.com/imagefiles/file/dowerumaju.pdfIn PDF document text
    • http://dent-pro.cz/pic/file/83684630181.pdfIn PDF document text
    • https://solucionaesp.com/ckfinder/userfiles/files/pubugumajejumikesax.pdfIn PDF document text
    • http://szyoujin.com/UploadFile/file/20210906233056238.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7217de57a---35920445138.pdfIn PDF document text
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/f850d2a45de233bb517bd5d4f09d1579/17343442578.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/niriwadegozufolamiwud.pdfIn PDF document text
    • https://btegypt.com/file/bunur.pdfIn PDF document text
    • http://xinxinhouseware.com/uploadfile/files/kokobaroz.pdfIn PDF document text
    • https://receptabc.hu/images_banner/files/kolelujenowizav.pdfIn PDF document text
    • https://www.retake.dk/ckfinder/userfiles/files/268253450.pdfIn PDF document text
    • http://cascinamana.it/userfiles/file/xepiluwifesidujizidixixoj.pdfIn PDF document text
    • https://cfi-registration.org/buzzboxgift/img/userfiles/files/87812489171.pdfIn PDF document text
    • http://ituor.ir/basefile/chartermeinfo/files/rivixetidipopufinoxixusi.pdfIn PDF document text
    • https://mayxaydungthienlong.com/uploads/files/files/kuxajeta.pdfIn PDF document text
    • http://iburgisidimarsala.eu/userfiles/files/mosukojefido.pdfIn PDF document text
    • https://mar3ol.com/Files/files/zavawivono.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614acc51d3db7---12228109029.pdfIn PDF document text
    • http://runhouchem.com/upload/files/ketizagikoripofekakivizo.pdfIn PDF document text
    • http://studiopol.com/userfiles/files/81208474659.pdfIn PDF document text
    • http://kdesignuk.com/userfiles/files/muwebejerafomerased.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_off0000b57b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB57B 15320 bytes
SHA-256: 5dfc63c98522bb5493e68fd0fee64fb59a51c0009de137fb40daf2d53d0b18a4
font_01_sfnt_off0000dc02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC02 10928 bytes
SHA-256: 0d7f2a21beebac78b9478c8427073ef59bcb07d3102d1bbe9c2b7a27d73027c4
font_02_sfnt_off0000f516.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF516 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1