Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5f3befe4d67fe61…

MALICIOUS

PDF

94.8 KB Created: 2021-09-04 13:15:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 9b5e9fb48a8c52817ed70c94660f8a39 SHA-1: 1932553f77390032139a6797559a5398723e837d SHA-256: a5f3befe4d67fe61a60a79c61755ae9446c70b3979bd6a832eacbd67eac277f8
176 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Numerous heuristics point to the use of link farms and compromised CMS uploads to host or redirect to malicious PDF files, often disguised with terms related to job recruitment. The presence of external URIs and IP literals further supports the distribution of malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://durgabas.coop.np/ckfinder/userfiles/files/vazorevowuxera.pdf In PDF document text
    • http://katour.ru/admin/ckfinder/userfiles/files/fedefiwitufita.pdfIn PDF document text
    • http://ladyvenus.it/userfiles/files/pevowopizuwozebowuxolav.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609c5c2fe70ef---gugidasedijerovevi.pdfIn PDF document text
    • http://gajagotour.com/UserFiles/file/saleki.pdfIn PDF document text
    • http://bsbcarpet.com/userfiles/file/rizakem.pdfIn PDF document text
    • http://157.230.241.115/image/upload/File/15636816057.pdfPDF link annotation
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/ba4058981b281cf0faf2308314a5b4b0/146601892.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/31105989349.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d61d8218f7a---83807227502.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/c834371181c934217b2fef39dc4d55fe/5110922768.pdfIn PDF document text
    • http://auto-spec.ca/fck/file/jonesomaxanasebukef.pdfIn PDF document text
    • http://ettermanenterprises.com/ckfinder/userfiles/files/26981893300.pdfIn PDF document text
    • http://flirdining.com/uploads/files/60113400488.pdfIn PDF document text
    • http://studiopassarotti.it/userfiles/files/tirolavawanamodezito.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/aec77fec36e9804b366fb9f121d866ba/56065649569.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/nadolekakapavu.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/55011d8841fbce42f106eb8a0a24d5df/putafebosegonififaj.pdfIn PDF document text
    • http://romovi.net/sgi_userfiles/userfiles/files/42892150432.pdfIn PDF document text
    • http://blackhorsesc.pl/userfiles/file/bisezaxubanorugipuvu.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f7cda1be00---dukevuvuxuge.pdfIn PDF document text
    • http://pusheng168.com/uploadfiles/20210620011345.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160739305933e0---lowemuxorabinitixemedefal.pdfIn PDF document text
    • https://agentcctv.com/userfiles/file/nebubofozajubenirumerisa.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/8g3g8mkgqq9qkk60bli2fmcg3f/65578051282.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=successful+interviewing+and+recruitment+pdfPDF 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_off00010b86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B86 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001239d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1239D 11172 bytes
SHA-256: e35b2a9f78591a74971afb70e0db511c667e78cb8c90089c5687dffe18b8583f
font_02_sfnt_off00013d8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D8C 18668 bytes
SHA-256: 4c5a1815a6607e4c9242fe1c4d3fc46a5ec1eff143b86233bfa25d092d7d02fe