Malicious PDF — malware analysis report

Static analysis result for SHA-256 53d31922b66a0982…

MALICIOUS

PDF

71.8 KB Created: 2021-09-15 19:44:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: aab37de0d0b9d70e25cf9c7bf39580f6 SHA-1: fe1b1ae0fc2ce97faf67d3dac7a57fba299a8428 SHA-256: 53d31922b66a0982e3c6d1fc8d66804c8a18e75793df44db91f956f65a09e7c1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier. It contains numerous links, many pointing to compromised WordPress upload directories or disposable hosting, suggesting a link farm intended to host or redirect to malicious content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics indicates a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://prevodi-plovdiv.com/userfiles/file/ruros.pdf In PDF document text
    • http://www.kigimex.com.vn/ckfinder/userfiles/files/nolob.pdfIn PDF document text
    • https://buonoantonio.it/userfiles/file/liderotamikew.pdfIn PDF document text
    • http://abwhopewell.com/uploads/files/nitunabufiwudesejirudul.pdfIn PDF document text
    • http://delannahotel.com/user_img/file/71571443014.pdfIn PDF document text
    • https://beldapromosyon.com/calisma2/files/uploads/pesatuzotajivitelaz.pdfIn PDF document text
    • https://jetaime-shop.dvsportbg.com/files/34114126704.pdfIn PDF document text
    • https://habrit.tw/ckfinder/userfiles/files/zoxelagisedar.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/161391a64ad2f8---moxopoluvuveno.pdfIn PDF document text
    • http://globalfeedindustry.com/upload/files/keluxifagoziziju.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/5f7no3q7abqt48htbamd1nsrh2/zosap.pdfIn PDF document text
    • https://terlickodds.cz/www/www/fckphotos/file/mejarep.pdfIn PDF document text
    • https://nilsahost.com/calisma2/files/uploads/1270003246.pdfIn PDF document text
    • https://hongming-eco.com/userfiles/file/jopufamum.pdfIn PDF document text
    • http://anquocrealty.com/uploads/image/files/58192688596.pdfIn PDF document text
    • https://krygina40.ru/UserFiles/File/95873067872.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/71990001535.pdfIn PDF document text
    • https://krafteco.ru/uploads/files/mibuwaxekivajewovepave.pdfIn PDF document text
    • https://abisspaandboutique.com/nbloom/fckuploads/file/48377331660.pdfIn PDF document text
    • http://nakamurasangyou.jp/app/webroot/uploads/files/7771198716.pdfIn PDF document text
    • https://wodepcb.cn/uploadfiles/files/2827837208.pdfIn PDF document text
    • http://vpecargo.com/userfiles/file/52516651481.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16130340940e80---luwideworebo.pdfIn PDF document text
    • http://a-swiss.com/upload/userfiles/file/5390262295.pdfIn PDF document text
    • https://toliveinchristjesus.ceosale.catholic.edu.au/application/third_party/ckfinder/userfiles/files/jolixezamekasidusizemi.pdfIn PDF document text
    • https://fallsplat.se/bildbank/file/vawadujazibofo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=kodi+version+19+addonsPDF 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_off0000bb57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB57 10376 bytes
SHA-256: 54b14fbcf374d57f01c97e97910386f7bd1d7e47b779c5716a1ac7a4773a563b
font_01_sfnt_off0000d301.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD301 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eb13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB13 15344 bytes
SHA-256: 775c0770bc5635f5d946d081032bb91864ed5b2ecc8a90576eb5f108393bb066