Malicious PDF — malware analysis report

Static analysis result for SHA-256 0541b8135fe011cd…

MALICIOUS

PDF

84.4 KB Created: 2021-08-07 06:35:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 09232f7906b9fa7a5aa764fc62d0d72e SHA-1: 7066bbc58b15ae0508de98174cc31cd84e545c11 SHA-256: 0541b8135fe011cd5de9374c960cc6832acfc4c5001ab5627beb28a04df0318e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on various domains, suggesting a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or distributing further malware. The presence of compromised CMS upload links further supports the malicious nature of the hosted content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://sca-eagleegg5k.com/ckfinder/triplebuserfiles/file/vigedi.pdf
    • https://successstudio.net/userfiles/file/lowenudagufenegixi.pdf
    • http://t-p-fortune.com/userfiles/file/xexifunade.pdf
    • http://xn--vb0b83rba554gca.kr/page_data/file/20210511201932.pdf
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608984557ad4c---taxom.pdf
    • http://videoacceso.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b231d92525d---86586874703.pdf
    • https://dbjadow.pl/attachments/file/kexajerilasenijak.pdf
    • http://praguetransfer.com/files/file/lufonugudolozebuzegil.pdf
    • https://minegociomiweb.com/userfiles/file/xisawajimifakipivoni.pdf
    • http://cuatudongsaigon.vn/uploads/files/95557698081.pdf
    • https://hondamienbac.vn/userfiles/file/72718107623.pdf
    • https://www.frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/nevinokilakolad.pdf
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d90dd26f333---rexijerudadu.pdf
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608b0dcc2198e---2741225298.pdf
    • http://vincentpopetutoring.com/clients/d/dd/dd6b7bcf94cac99d3bed97cf8166637b/File/19319128856.pdf
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/c6pvkq5neqt6t78vd8p9o4qb05/54827445698.pdf
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/160da8a2d81d08---vewowor.pdf
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/ab956702e6b3e51292daaa7c550796a8/wasufarafadulumiwi.pdf
    • https://aihr-iadh.org/uploads/FCK_files/file/jitafo.pdf
    • https://tylbm.com/Upload/ckeditor/files/zujuvirasekodevemi.pdf
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/b640b2307c2d526f8beb6aefd88d854f/54371329941.pdf
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ada7a9ed775---73628038702.pdf
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/1b140d252b7c2079cd643997c8ccf846/38420788704.pdf
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c984cce7bdd---33052005612.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=que+tipo+de+enlaces+es+el+acido+sulfurico
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e410.bin
bb556265e01ccb8413d6ea995a2a75c5420e54e595a3df0fcc00414f1d77ea1f
pdf-font-stream PDF embedded font (sfnt) at offset 0xE410 17816 bytes
font_01_sfnt_off00011149.bin
bdfc05173c0ea61d3a99a753cc19ba736b3364c5bc139712f727c071948e2d28
pdf-font-stream PDF embedded font (sfnt) at offset 0x11149 10772 bytes
font_02_sfnt_off00012a48.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12A48 16792 bytes