Malicious PDF — malware analysis report

Static analysis result for SHA-256 2f829c2a1857e915…

MALICIOUS

PDF

84.9 KB Created: 2021-09-15 13:20:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f1c8a3aab838e1f4c043bfaf16493a48 SHA-1: 4ac066e9ec70296b79fbfb04a6b92a4f8d76d35d SHA-256: 2f829c2a1857e9153f90f63bd295112373cff6d0b4036b42a5fc80b3d38cc109
126 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to other PDF files hosted on various domains, indicating a link farm designed to obscure the ultimate destination. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, noting the use of disposable hosting and UTM parameters in some URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://noospc.ru/SITE/files/editor/file/wuwerajasijajufejabujo.pdf In PDF document text
    • http://thehedgerowchronicles.com/ckfinder/userfiles/files/1445356141.pdfIn PDF document text
    • http://tndgdemo2.com/ckfinder/userfiles/files/82446094373.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/16137b6ee81ed7---renorebubizitapofezag.pdfIn PDF document text
    • https://conrays.ru/f/data/62892868535.pdfIn PDF document text
    • http://kochamsushi.pl/UserFiles/file/dolibefizowinarevuxa.pdfIn PDF document text
    • http://professional-tuner.at/uploaded/file/xajuroronaxidibalukow.pdfIn PDF document text
    • http://optometrystaprzemysl.pl/userfiles/file/fopejunomenasojuwados.pdfIn PDF document text
    • http://cathyknightwaite.com/ckfinder/userfiles/files/ritigiseziraxirakifaw.pdfIn PDF document text
    • http://wsp.pl/userfiles/file/bijaxiduposofi.pdfIn PDF document text
    • http://thebeautyofdesign.nl/ckfinder/userfiles/files/70835592349.pdfIn PDF document text
    • https://subded.org/userfiles/file/62109915210.pdfIn PDF document text
    • http://taihegas.com/filespath/files/20210910010203.pdfIn PDF document text
    • http://covina.crazyrockinsushi.com/uploads/files/92677732122.pdfIn PDF document text
    • http://gowowdeli.com/uploads/files/gefugolejoj.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613510821cd63---tosozelegeganad.pdfIn PDF document text
    • https://foodexgida.com/uploads/files/vivav.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe1998535b---57540633566.pdfIn PDF document text
    • http://smcertificationservices.com/userfiles/files/41930894412.pdfIn PDF document text
    • http://ambvet-trefontane.eu/userfiles/files/butidatibusivebimelat.pdfIn PDF document text
    • http://daisytalavera.com/userfiles/files/30917480332.pdfIn PDF document text
    • https://exam11.menapoint.com/app/webroot/upload/files/95626029981.pdfIn PDF document text
    • http://pwr-tech.ru/userfiles/file/86821373420.pdfIn PDF document text
    • https://vibangthuaphatlai.net/uploads/files/kekedolawu.pdfIn PDF document text
    • http://importfoodfair.com/userfiles/image/2021/09/file/gejewamom.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=8+ball+pool+mod+menuPDF 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_off0000e67a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE67A 10444 bytes
SHA-256: 4c951500e59702f0c9ab76715d7c38d26516e15fddebcf1a823840f2613f7e7b
font_01_sfnt_off0000fddc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDDC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000115ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115EE 18592 bytes
SHA-256: d5e9dde173279965c30f299478965f9a0d6bd44a437b4a8dc35e5bda89144529