Malicious PDF — malware analysis report

Static analysis result for SHA-256 87099de1100fa8fe…

MALICIOUS

PDF

73.0 KB Created: 2021-09-25 23:20:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 97eb9cd16864e9562f104ec6b6ca7290 SHA-1: 5864ad830379eb302e457c8b16ae9b1fee60311d SHA-256: 87099de1100fa8fe19e28b277e905ebaf5bb885f2b229aa7351d73de92fa96bd
126 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9940

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 https://nomylo.ru/uplcv?utm_term=find+the+sum+of+the+first+10+terms+of+the+arithmetic+sequence PDF link annotation
    • https://latgalesamatnieki.lv/files/file/97027738768.pdfIn PDF document text
    • https://lenaoyunlar.com/calisma2/files/uploads/niluruzalatigereda.pdfIn PDF document text
    • http://abnicum.com/files/file/sekifowobudalule.pdfIn PDF document text
    • http://surausa.com/uploads/files/7255262422.pdfIn PDF document text
    • http://minhanh.com/files/88911923219.pdfIn PDF document text
    • http://kxxbs.com/uploadfiles/file/a/wutel.pdfIn PDF document text
    • http://cistenivytahu.cz/upload/file/taxiwarew.pdfIn PDF document text
    • https://venusnvs.com/userfiles/file/tapumabuzu.pdfIn PDF document text
    • https://euforbiabulgaria.gbinvest.net/uploads/pages/files/73879978858.pdfIn PDF document text
    • http://foto-recepty.sk/images/fotky/lugibiwu.pdfIn PDF document text
    • https://catequesisnavarra.org/guiarte_userfiles/files/fomuw.pdfIn PDF document text
    • http://china-zub.ru/userfiles/file/kevabusakiwapi.pdfIn PDF document text
    • http://cokhixnktientien.com/Images_upload/files/55257385350.pdfIn PDF document text
    • https://serviceservice.eu/userfiles/file/digutizuso.pdfIn PDF document text
    • http://alsace.annuaire-regional.com/ckfinder/userfiles/files/tugim.pdfIn PDF document text
    • http://ibconsulting.it/userfiles/files/39064229438.pdfIn PDF document text
    • http://laptopplus.be/app/webroot/files/userfiles/files/digavuzaduveme.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161410ff66fab1---50946293565.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/5ce7a7jfv9auh8f8dh0956gmf5/11214716788.pdfIn PDF document text
    • http://vector-mebel.ru/uploads/files/89464076131.pdfIn PDF document text
    • http://shesob.com/file/files/polexupajotanotimidew.pdfIn PDF document text
    • http://gioiacompany.net/images/upload/file/71026061264.pdfIn PDF document text
    • http://sculecuacumulator.ro/app/webroot/files/userfiles/files/68957978671.pdfIn PDF document text
    • http://fertilityupdates.com/userfiles/files/pokozoronewawivemiz.pdfIn PDF document text
    • https://cincia.ro/ckfinder/userfiles/files/nemexem.pdfIn PDF document text
    • https://kuepancong.com/contents/files/mujosisezumijakabaxujiwo.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_off0000b7c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7C1 11092 bytes
SHA-256: 08e7de9bdb690b636127ba9b361ab4b0a390dcf54cf96b951bf78beb792a1bc6
font_01_sfnt_off0000d13e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD13E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e950.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE950 17468 bytes
SHA-256: de30863aa6b15060a3679b1a2f21ebe1907c21cdc855527b1c504401a4044699