Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef5a6c986cddb171…

MALICIOUS

PDF

73.8 KB Created: 2021-09-20 14:06:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 200a717cac5ce59502c3e444fc78a718 SHA-1: af433c3335a87b694db627865bb5f3f2e67e2039 SHA-256: ef5a6c986cddb1718bd4530207db0d05f01f0e27440a54ffe9061ea5bb32224a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable domains and are part of a link farm, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links are consistent with techniques used to redirect users to malicious sites, potentially for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://sibmaxi.ru/userfiles/file/rojujebupamilale.pdf In PDF document text
    • http://prplus4u.com/ckupload/files/salemagoxebepidelidat.pdfIn PDF document text
    • http://usateatop.com/_upload/files/xakowegadasatasudezetil.pdfIn PDF document text
    • https://resicolor.com/upload/files/pakidufiraxabapuwirajot.pdfIn PDF document text
    • http://soepcentrale-dekeyser.be/userfiles/file/fuzogelijujatiwaxot.pdfIn PDF document text
    • https://nnt52.ru/userfiles/file/jowabimetivivisapifenisem.pdfIn PDF document text
    • http://pop-around.com/file_media/file_image/file/rafetalalomiripema.pdfIn PDF document text
    • http://www.nagsa.es/ckfinder/userfiles/files/10768293761.pdfIn PDF document text
    • http://intrinhgia.com/admin/webroot/upload/image/files/71991699030.pdfIn PDF document text
    • http://nurugelexport.com/ckfinder/userfiles/files/51944670536.pdfIn PDF document text
    • http://stilna-ya.com/_userfiles/file/tudije.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138cc43e2be0---46540800566.pdfIn PDF document text
    • https://amthanhanhsangchinhhang.vn/upload/files/pakaxubatomew.pdfIn PDF document text
    • https://mimpiindah168.com/contents/files/navizazonuxegavukerogij.pdfIn PDF document text
    • https://vgi-vn.vn/app/webroot/img/files/vujizawasasisibis.pdfIn PDF document text
    • https://noriupapildu.lt/ckfinder/userfiles/files/68852831796.pdfIn PDF document text
    • http://baby-daycare.com/uploads/files/202109170754085264.pdfIn PDF document text
    • https://sowlindia.com/userfiles/file/susakuwusexakomawevo.pdfIn PDF document text
    • http://xn--80aafkatcapceshpicpg3h.xn--p1ai/pict/file/18364498939.pdfIn PDF document text
    • http://carlaschroyen.com/content_docs/ridupiguzixavago.pdfIn PDF document text
    • http://turnwealthy.com/ckfinder/userfiles/files/dufebavuxetotubub.pdfIn PDF document text
    • http://a-mega.ua/images/uploads/file/kinagusosemotepomunagud.pdfIn PDF document text
    • http://kooijobs.in/ckfinder/userfiles/files/49182290944.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613f6e7982d63---denavojegejixevusawusej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=flora+font+apkPDF 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_off0000beaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBEAA 17272 bytes
SHA-256: 312639e4b3f68c922f1b9beeb0f3b4c89e04726eb1fc77b3c9d20fbe5e191a72
font_01_sfnt_off0000eb2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB2C 10028 bytes
SHA-256: 60907a652c02ccb454cf4cc16770090c0a82b8e6b548400907a88da739754d6d
font_02_sfnt_off00010188.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10188 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1