Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f39acbdd2cc32e3…

MALICIOUS

PDF

70.6 KB Created: 2021-09-09 02:55:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5c24dc49dd142131004b65339d99f184 SHA-1: 290a7aee8cb350575207e3fb530024c30c787401 SHA-256: 1f39acbdd2cc32e3713625d5d1d8fbe6f0bb41944de8ec36b10f37c9395e6425
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous embedded URLs pointing to other PDF files hosted on various domains, some of which appear to be compromised or disposable. This pattern suggests an attempt to lure users to external malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://otohondamientay.com/upload/files/labutojajazufaxazob.pdf In PDF document text
    • http://seoulsquare.com/userfiles/file/22336616684.pdfIn PDF document text
    • http://panova-art.com/files/file/56531189.pdfIn PDF document text
    • https://bvphcn.bdata.vn/upload/files/vugewed.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16131658c20521---32242907073.pdfIn PDF document text
    • http://penzionnakrizankach.cz/ckfinder/userfiles/files/73900443096.pdfIn PDF document text
    • http://chinhlytailieuluutru.com/media/ftp/file/85074290095.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/b64fde2946f774090294d1f306893f60/zizozujanuk.pdfIn PDF document text
    • https://raselapp.com/userfiles/file/64250925131.pdfIn PDF document text
    • https://sibservis.com/ckfinder/userfiles/files/64481039411.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/161369e50f2d34---58834832474.pdfIn PDF document text
    • http://galantemontagnana.it/ckfinder/userfiles/files/dafurozoruzapave.pdfIn PDF document text
    • http://bkht.vn/userfiles/file/67050581004.pdfIn PDF document text
    • https://matfplayer.com/calisma2/files/uploads/8460075852.pdfIn PDF document text
    • http://www.dkmodels.net/ckfinder/userfiles/files/gozud.pdfIn PDF document text
    • http://xfswchem.com/upload/files/sedugefanuzijefe.pdfIn PDF document text
    • https://voziky-paletove.cz/mctree.cz/pictures/other/files/xeruli.pdfIn PDF document text
    • http://emanuelarombiarchitetto.eu/userfiles/files/28021948210.pdfIn PDF document text
    • https://classykitchen.pl/web/uploads/files/fajixefuxubumife.pdfIn PDF document text
    • http://abwnickersonplaza.com/uploads/files/89102682780.pdfIn PDF document text
    • http://moscowfashion.net/content/xuploadimages/file/83774729856.pdfIn PDF document text
    • http://status-go.net/gfx/userfiles/files/4692864273.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613424ed7561f---67124480690.pdfIn PDF document text
    • http://mptech.vn/ckfinder/userfiles/files/tomuporozexufej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=heroes+rising+putlockerPDF 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_off0000b7b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7B0 10572 bytes
SHA-256: 13fa375eae715a5e0824edeb171d41a0bd36e37d977f7401307539aee642053c
font_01_sfnt_off0000cfeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFEB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e7fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7FD 14520 bytes
SHA-256: 0693aba313384e006ef880326f56519d7ced94eb690307d63599e3724581d47e