Malicious PDF — malware analysis report

Static analysis result for SHA-256 da6fc731594dee6a…

MALICIOUS

PDF

74.8 KB Created: 2021-09-04 10:06:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 5fc46fbaf4fd624a719903dbdf8b3da0 SHA-1: dd885326879397adc4402be93ab415eb8207dbc8 SHA-256: da6fc731594dee6a01812c7b31470d577f9407cd8e7e51c2d1784d6d22f98e32
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many hosted on compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution lure, likely leveraging embedded JavaScript for redirection or exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://wastran.ru/uplcv?utm_term=free+piano+sheet+music+pdf+all+of+me PDF link annotation
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1609a2d3db14f0---rosibabavapurufem.pdfIn PDF document text
    • http://tradeweb.es/userfiles/file/25008961165.pdfIn PDF document text
    • https://atkarisuli.hu/userfiles/file/gexeselowilede.pdfIn PDF document text
    • http://allasclub.com/campannas/file/jikegoles.pdfIn PDF document text
    • https://larrialdiak.es/files/galeria/files/fiwesisotijowetakajimureg.pdfIn PDF document text
    • http://allseasonsart.com/uploads/fck_uploads/file/43985514198.pdfIn PDF document text
    • http://innova-perila.ru/upload/files/fowumabijixepaxikunivo.pdfIn PDF document text
    • https://bozoklar.org/ckfinder/userfiles/files/kefunotelowirevidenozigal.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160acf3ef5d613---zarojaromireme.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/cbc1868c5fe00a15a0dcab5bfa49d9d1/kafomow.pdfIn PDF document text
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/732i5pa2u0840c7bsprs3vv3j0/93007035067.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/f909a400ab0f771d2fa27e020e30c5f9/45785369137.pdfIn PDF document text
    • https://inunekocp.jp/mailmagazine/upload/files/33009881172.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/41406849116.pdfIn PDF document text
    • https://www.gico.ge/ckfinder/userfiles/files/fumemufutubixuw.pdfIn PDF document text
    • http://grupophi.es/uploads/files/3925112548.pdfIn PDF document text
    • http://popnmusic.fr/userfiles/file/1898334822.pdfIn PDF document text
    • https://eagle-aviation.com/userfiles/files/wawunulabudowoviboxa.pdfIn PDF document text
    • https://study-abroad-travel.com/ckfinder/userfiles/file/94586797674.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160764124eb136---3146640931.pdfIn PDF document text
    • http://www.accl-calibration.com/login/ckfinder/userfiles/files/70588409263.pdfIn PDF document text
    • http://archissimo.eu/userfiles/files/xixozoduxar.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/dexelevanudav.pdfIn PDF document text
    • https://bisnismedsos.com/userfiles/file/97839095986.pdfIn PDF document text
    • http://zhihepvb.com/upload/ckimg/files/202108022054327722.pdfIn PDF document text
    • http://sinproval.it/userfiles/files/13830949991.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_off0000c07e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC07E 17100 bytes
SHA-256: 2f7f3bab742b2baf5aaf26102c24f14de334a85318f96f81c11113a42344cdd4
font_01_sfnt_off0000ec2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC2F 10960 bytes
SHA-256: 523a29455af7284b0951ce6f157a5bb372365393df61a325fe9004376ce17c05
font_02_sfnt_off0001055e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1055E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1