Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8692e75356b0d7d…

MALICIOUS

PDF

79.6 KB Created: 2021-09-16 17:33:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 03d4b7d7400e60c22904e907a277ab01 SHA-1: 3c5160447f3c3254ef876c773ac1faea245f6d8a SHA-256: a8692e75356b0d7d34daef9dba15e76c55c9a2e75e48174980a56684ea3c7047
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to potentially compromised websites or disposable hosting, indicative of a link farm designed to redirect users. Heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest this malicious intent. The ClamAV detection and ML classifier further confirm its malicious nature, likely serving as a lure for phishing or malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://crewmak.ru/uplcv?utm_term=funzpoints+apk+download PDF link annotation
    • http://adamlegal.com/userfiles/file/wufunevigimesigusapova.pdfIn PDF document text
    • http://artio.pl/files/files/95226417932.pdfIn PDF document text
    • http://elturo.ru/img/upload/files/99283985386.pdfIn PDF document text
    • http://temdientu.vn/images/ckeditor/files/27453796766.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134a77caed89---51820995325.pdfIn PDF document text
    • http://gro-felix.si/uploads/nizivosaregotasigu.pdfIn PDF document text
    • https://byocamacho.com/ckfinder/userfiles/files/ganedojov.pdfIn PDF document text
    • http://radiosalsa.fr/php/rs/filesupload/file/41125692232.pdfIn PDF document text
    • https://hoatuoi360.vn/uploads/files/vimitir.pdfIn PDF document text
    • http://aligokdemir.com/resimler/files/41995736028.pdfIn PDF document text
    • https://weeb.nu/userfiles/file/59544554049.pdfIn PDF document text
    • http://liebherr-tr.com/userfiles/file/3617445833.pdfIn PDF document text
    • http://bongoes62.dk/userfiles/file/legiminowawizozanas.pdfIn PDF document text
    • http://bjhtdszdh.com/v15/Upload/file/2021921024203670.pdfIn PDF document text
    • http://dblbtech.com/userfiles/file/31899647883.pdfIn PDF document text
    • http://teusz.pl/UserFiles/file/57049068192.pdfIn PDF document text
    • http://mikllc.mn/uploads/files/80734447739.pdfIn PDF document text
    • https://vasutaszeneiskola.hu/ckfinder/userfiles/files/16597849999.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/90a0bf5f059296ff2d664e151aa2d10b/89970848034.pdfIn PDF document text
    • http://zhizhencn.com/filespath/files/20210911021617.pdfIn PDF document text
    • https://aymexco.eu/ckfinder/userfiles/files/vijoxorugi.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161424de853897---rijadasarulonaziror.pdfIn PDF document text
    • http://ride.hu/images/uploads/files/jarenorovub.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_off0000d2ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2AB 18076 bytes
SHA-256: 2d36eb6ee2822830b59da3ccf116128b331fe3735ea11ad8a8f3a13a20594175
font_01_sfnt_off000100da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000118f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118F1 10468 bytes
SHA-256: 5ea05672922810d5c5ddf2bcbb3b7e9dfbb42a15d36f9d7cc1eba8b90b28251a