Malicious PDF — malware analysis report

Static analysis result for SHA-256 bff801d81f666ce8…

MALICIOUS

PDF

77.5 KB Created: 2021-09-16 06:48:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 36c6f62a315963b7bf1a3887d9cb1baf SHA-1: a6bd468c762efd2000336fa8e5773d03fec54753 SHA-256: bff801d81f666ce8557cc520f53cb56a04cfd2a643fd9a50279a9c3b9c65d59a
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which are part of a link farm, suggesting a phishing or malware distribution scheme. The presence of a 'download button' heuristic further supports the idea that the PDF is designed to trick users into downloading a payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://nomylo.ru/uplcv?utm_term=cat+simulator+unblocked PDF link annotation
    • http://architettogherardi.eu/userfiles/files/gozifaribokulu.pdfIn PDF document text
    • http://tcsklife.com/filespath/files/20210905205001.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/50815381329.pdfIn PDF document text
    • https://sunwayhk.com/louis/STARKGROUP/ckfinder/userfiles/files/susomesowaburitozezuteb.pdfIn PDF document text
    • http://gleb777.com/fck_upload/file/58840239845.pdfIn PDF document text
    • http://westfallassociates.com/documents/file/20127729641.pdfIn PDF document text
    • https://www.bbmnetlicitacoes.com.br/cms/ckfinder/upload/files/petujuw.pdfIn PDF document text
    • http://unite-chem.cn/upload/files/35346869209.pdfIn PDF document text
    • https://stalbeckers.nl/userfiles/image/file/sesebena.pdfIn PDF document text
    • http://naasschoolofmotoring.com/fckeditor/userfiles/file/60978929388.pdfIn PDF document text
    • http://thietbiotoviet.com/Images_upload/files/jebeveb.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613883702600c---xepasenexisemumide.pdfIn PDF document text
    • http://kirsanov-maslo.ru/uploads/72517233312.pdfIn PDF document text
    • http://inspiredindianfoundation.org/uploads/23015222847.pdfIn PDF document text
    • https://www.totalblissbeauty.com.au/application/third_party/ckfinder/userfiles/files/jopatoleminuxatoli.pdfIn PDF document text
    • http://borik.customreal.sk/data/files/debururepunapidimusego.pdfIn PDF document text
    • http://triatlonbizuterie.cz/sites/default/files/file/82408190535.pdfIn PDF document text
    • https://mamap.in/ci/userfiles/files/49763651151.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/16134fa5f52bbd---57690109429.pdfIn PDF document text
    • http://wagnerpc.com/userfiles/files/bowem.pdfIn PDF document text
    • http://tovicetour.com/FileData/ckfinder/files/20210911_5A7B150977AF78F2.pdfIn PDF document text
    • https://navoloki.mebel18.com/uploads/files/nuxawunidapowizejeratun.pdfIn PDF document text
    • http://joy05.com/_UploadFile/Images/file/18291011419.pdfIn PDF document text
    • http://kanalizace-ul.cz/userfiles/file/dipodir.pdfIn PDF document text
    • https://campfun.myhost888.com/upload/ckeditor/files/65796930398.pdfIn PDF document text
    • 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_off0000ca81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA81 17012 bytes
SHA-256: 892cfc6a2c6f085e77390ca35f05c2a230fcfeaf746c15c326e06e8d65675533
font_01_sfnt_off0000f6f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6F3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F0A 10896 bytes
SHA-256: cc947c8263bea21d02f8c5cb678564a6e0e4b69c36210785249f3ef854f98432