Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa8c917671b244e0…

MALICIOUS

PDF

84.3 KB Created: 2021-09-23 02:09:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ac52ee9dc1b97c9c74a77ee79fc31c16 SHA-1: 68d406a80e3b1aa1f5802db162c94887b7b86ad9 SHA-256: aa8c917671b244e089122b037c89e320d9bcd4e4653621c19c36c7f01babea2f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs that point to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users to malicious sites. While no scripts were explicitly extracted, the nature of the URLs and the 'link farm' heuristic strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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
  • 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://oniceh.ru/uplcv?utm_term=view+anonymously+instagram+reels PDF link annotation
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/vaq9at5k03tvm8eskbbu34g2p5/37557124281.pdfIn PDF document text
    • http://vocal.bpv.su/content/files/files/guwegedarediluwomosapi.pdfIn PDF document text
    • https://lrsdev.com/userfiles/file/wowadigitupaxelubodub.pdfIn PDF document text
    • http://e-sportis.com/images/upload/32542312027.pdfIn PDF document text
    • https://nmcs.ca/userfiles/files/xilurirexuze.pdfIn PDF document text
    • https://shiprapublication.com/uniformkontakt/userfiles/image/files/75818916470.pdfIn PDF document text
    • https://hobbyschuurtje-webwinkel.be/images/userfiles/file/vujovatamunegive.pdfIn PDF document text
    • http://cansuyu.org/resimler/files/sexuwuj.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021091615583119.pdfIn PDF document text
    • https://himalayanwanderer.com/himalayan/userfiles/files/venujeles.pdfIn PDF document text
    • http://jts-electrical.co.uk/ckfinder/userfiles/files/64094132144.pdfIn PDF document text
    • http://ap-qatar.com/userfiles/files/mumapugar.pdfIn PDF document text
    • http://china-engine.net/ckfinder/userfiles/files/digavigijuvuwugo.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613dd1aae79b1---marodawumuriwurafig.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/0p3oaba5dsnpi1uccpp7vvb7m1/56402655552.pdfIn PDF document text
    • https://extremedriveline.com/ckfinder/userfiles/files/kurovevujodokegakotal.pdfIn PDF document text
    • http://nhakhoasaigonkimcuong.com/uploads/images/files/mukuvazivosaninove.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/e46ba6d4e20990a2d3a6df6d1a2c803d/54868929171.pdfIn PDF document text
    • https://arerp.kr/data/file///54545368577.pdfIn PDF document text
    • http://suvenirzp.com/uploads/files/98976871582.pdfIn PDF document text
    • http://energo-market.ru/sadm_files/40712502318.pdfIn PDF document text
    • http://szwygs.com/upload/tobelowomifaw.pdfIn PDF document text
    • http://exmar.it/foto_fck/file/pajanixoxulubadokesopo.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_off0000dcc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCC5 20200 bytes
SHA-256: 3620eb153af01714cfaf726040137ac0488bb41e0c6faaf85d8efd8fc9f81a5a
font_01_sfnt_off00011160.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11160 10720 bytes
SHA-256: a288854533010ffa67d31b8b962a5e83560ff398ec67c06babf5fad3a810ec37
font_02_sfnt_off00012a19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A19 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1