Malicious PDF — malware analysis report

Static analysis result for SHA-256 09896bc77ae18ee5…

MALICIOUS

PDF

67.8 KB Created: 2021-09-10 21:50:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 8b3dbc09eefe6f4b8ef0e4c58d93e1b0 SHA-1: aceca1fd02fe2967108886174d333532c42dc2ac SHA-256: 09896bc77ae18ee57eed40c037310ddd9e225fde428b81c3fe514f54d613a8b8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm designed to redirect users through multiple domains, including compromised CMS uploads and disposable hosting, ultimately aiming to lead them to a specific download. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution, disguised as a legitimate download link. No scripts were extracted, but the PDF structure and URL analysis point to a social engineering attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://liepasmuiza.lv/userfiles/library/tixewedosizolufibe.pdf In PDF document text
    • http://mbfeed.vn/upload/files/deriwakeliribabapenejoxo.pdfIn PDF document text
    • http://crystaltrade.hu/data/file/vowoxowigod.pdfIn PDF document text
    • http://boathousebrokerage.com/userfiles/file/11122590369.pdfIn PDF document text
    • http://ohappy.org/userData/board/file/47664117530.pdfIn PDF document text
    • http://parvazyab.net/basefile/api203/files/xodawopo.pdfIn PDF document text
    • https://studioconcept-stand.com/fck_userfiles/file/78700972353.pdfIn PDF document text
    • https://farmacieitaliane.com/documenti/file/84513643492.pdfIn PDF document text
    • http://stefanourso.com/public/userfiles/file/64371833918.pdfIn PDF document text
    • https://polresseluma.com/assets/ckfinder/core/connector/php/uploads/files/wovofipoki.pdfIn PDF document text
    • https://robodom.si/files_vsebine/vusegifexerijogokovi.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613691caf1444---xukibitaleporozulugu.pdfIn PDF document text
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe0e6f1548---99753004803.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613b10f00c785---sekewurit.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b95d29c57f---navedizopovavoxiziwepibuj.pdfIn PDF document text
    • http://ambvetbrashersclavoghisu.eu/userfiles/files/51244279892.pdfIn PDF document text
    • http://marcobernini.it/userfiles/files/6367317891.pdfIn PDF document text
    • https://alves.bg/ckfinder/userfiles/files/8230879256.pdfIn PDF document text
    • http://palaciodelosnavas.com/userfiles/file/morusalefexelego.pdfIn PDF document text
    • http://clainvest.pl/userfiles/file/giruzetiwujobo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=camscanner+android+app+downloadPDF 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_off0000acdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xACDF 14492 bytes
SHA-256: d36a1a2115f2ae32ca1f23d280ee1115450bd2a8782ea4f4a60ffc4bde6852ee
font_01_sfnt_off0000d13e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD13E 10696 bytes
SHA-256: 8e245b8e3fb0ea1e5b4c60d0a38c471e5e3742129f8d7c1355014dbdc113f3d8
font_02_sfnt_off0000e9c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1