Malicious PDF — malware analysis report

Static analysis result for SHA-256 a61c9c1ed71d4f2e…

MALICIOUS

PDF

79.3 KB Created: 2021-09-01 17:18:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 363b41ae9ffc318f682907aad7a941ed SHA-1: c156275d72e4dc29cfb012f368812534107841c0 SHA-256: a61c9c1ed71d4f2ed3a3931e6c231f92654f51b325f5c41702561b3bcacee903
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to compromised WordPress upload storage and other disposable hosting, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and link farm nature are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://gimnazjum-krasiczyn.pl/img/userfiles/file/81054477108.pdf In PDF document text
    • http://se-ty.ru/uploads/userfiles/file/85128697189.pdfIn PDF document text
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/iecnnl43gme7em3gsgqc3te1gv/27457047756.pdfIn PDF document text
    • http://resetimpianti.it/reset/public/file/muxojevotegujones.pdfIn PDF document text
    • http://messtores.ca/fck_user_files/file/wepumi.pdfIn PDF document text
    • http://wingmanplanningdemo.com/userfiles/files/tilitigefonijipizuruli.pdfIn PDF document text
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/241f6e700da73295ae4b1a10f083e087/46607517787.pdfIn PDF document text
    • http://oryginalnedekoracje.pl/userfiles/file/30729475659.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/16119cb5e0303e---xekuvusogamorizatadasagud.pdfIn PDF document text
    • https://www.weboonline.com/ckfinder/userfiles/files/zumawevado.pdfIn PDF document text
    • http://imi.vc/upload/files/5924627261.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/4b6190a2508b56503e083945765b740f/boretovaraf.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16073a9ff39bf5---lewuruninazeropawu.pdfIn PDF document text
    • http://crmloccitanecr.com/campannas/file/xereroxow.pdfIn PDF document text
    • http://hanhthien.net/uploads/file/72969634267.pdfIn PDF document text
    • http://vigen12.com/userfiles/file/difejejulifedij.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/pigunatulibijefi.pdfIn PDF document text
    • https://www.assofmt.org/ckfinder/userfiles/files/bupunofajagunifudowamapem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=how+long+does+bls+training+lastPDF 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_off0000d222.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD222 10640 bytes
SHA-256: 54757428d64735d1c11ce3af70b727631ea6848b6fdbfca147e63033a71d8731
font_01_sfnt_off0000ea6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA6A 17836 bytes
SHA-256: 8f34e2e7e3944594889198fa87e4e751a2eb10f272be3fad2281f19a00a4eb06
font_02_sfnt_off00011869.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11869 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1