Malicious PDF — malware analysis report

Static analysis result for SHA-256 145b6f1bd31e8e87…

MALICIOUS

PDF

120.2 KB Created: 2021-09-17 00:11:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2864f29664ddb96ca6d6bab127f36bd8 SHA-1: dd558e553c56cdbf911da60ff7b23dc28e3b2fff SHA-256: 145b6f1bd31e8e8783bc2fe821f411da1d278dd6736e9ea711b0b7b8f8961769
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF containing numerous links, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL analysis point towards an attempt to exploit users via malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://burkina-businessschool.com/business_school/uploads/file/velobimupubixus.pdf In PDF document text
    • http://abpjseah.news-read.com/upload/files/pupetisegimukozas.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613bedcf66f33---80375010166.pdfIn PDF document text
    • http://inbjnews.com/data/cheditor/0603/files/kogusugeros.pdfIn PDF document text
    • http://musik-fachberatung-neumarkt.de/images/uploadedimages/file/23310700320.pdfIn PDF document text
    • https://citronixdeflection.com/nbloom/fckuploads/file/kozeles.pdfIn PDF document text
    • https://easypayindia.in/userfiles/file/86605901675.pdfIn PDF document text
    • https://negaratoto.com/contents/files/pixerawanege.pdfIn PDF document text
    • http://i-tos.com/userData/board/file/sijazajakovigize.pdfIn PDF document text
    • http://1544-7419.net/upload/fckeditor/file/8182025175.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/busnh8igvek7uas2v7ov3m4bid/tijojesixudusosozuwuxodo.pdfIn PDF document text
    • http://spzpoz-zdunskawola.pl/upload/file/43861322984.pdfIn PDF document text
    • https://sikdercollegeofpharmacy.com/scp/ckfinder/uploads/userfiles/files/bowufamoxifuz.pdfIn PDF document text
    • http://emachn.com/data/attachment/file/31771594039.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb9894561c---59985335316.pdfIn PDF document text
    • http://galerie45.com/userfiles/file/74664869035.pdfIn PDF document text
    • https://www.institutvzdelavani.cz/files/nikeduguwepetoruw.pdfIn PDF document text
    • https://hongming-eco.com/userfiles/file/69345540406.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/96064336813.pdfIn PDF document text
    • http://vhz.cz/user-files/rifizewokexem.pdfIn PDF document text
    • https://institut-arabe.org/ckfinder/userfiles/files/85226594892.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=ninja+run+old+gamePDF 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_off0001729f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1729F 10532 bytes
SHA-256: 1ec118e985cf6079b67a4251f34eb6aa9aacac262467f85501e664f927d307f8
font_01_sfnt_off00018a39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18A39 18724 bytes
SHA-256: 7058e93db371046bb12f7896ac576131f2f256d30d6453b795bb497f6a2a73f4
font_02_sfnt_off0001bbad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BBAD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1