Malicious PDF — malware analysis report

Static analysis result for SHA-256 751bcdeb7cf70edd…

MALICIOUS

PDF

81.5 KB Created: 2021-09-10 15:44:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 5510c2c1e2fdd4030587e64237e35c43 SHA-1: 5d8beb3922b2dd7d36536e73e374d1d58454c257 SHA-256: 751bcdeb7cf70edd38c3e7c915b4a48e65b43d7892f183a7d1edb17471060880
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or obfuscate the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pistant.ru/uplcv?utm_term=programa+para+controlar+pc+desde+celular+android PDF link annotation
    • http://lapenya.cat/imgjovesnaves/file/77930506306.pdfIn PDF document text
    • http://uniondrygoods.com/fckeditor/userfiles/file/walewujavutulazuzoluku.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613acb787f8ae---biberemevefalu.pdfIn PDF document text
    • https://mkontakt.pl/dat/file/78748001830.pdfIn PDF document text
    • http://associatedreclaimed.com/userfiles/files/78775916961.pdfIn PDF document text
    • https://gameadvisers.com/js/new/fckeditor/userfiles/file/35789080702.pdfIn PDF document text
    • http://sanraimundo.cl/dyn/uploads/file/38671734380.pdfIn PDF document text
    • http://geometracosentino.com/userfiles/files/65937348363.pdfIn PDF document text
    • https://www.ccs-corporation.com/ckfinder/userfiles/files/nolusosexur.pdfIn PDF document text
    • http://musicincw.com/fckeditor/userfiles/image/ligigakunizuti.pdfIn PDF document text
    • http://eyela.kr/uploadfile/fckeditor/file/49510962960.pdfIn PDF document text
    • http://mobydick-band.de/fckdata/file/dewosilinala.pdfIn PDF document text
    • http://oipipleszno.pl/userfiles/file/medatejarod.pdfIn PDF document text
    • http://xn--54-dlcdkamdj4btild5b.xn--p1ai/ckfinder/userfiles/files/gumasomujexolabevu.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/6a517f375a47245c2a30996121287228/19471418144.pdfIn PDF document text
    • https://mbzgogo.xyz/web/img/podborky/files/30847719584.pdfIn PDF document text
    • http://veiligheidssloten.nl/ckfinder/userfiles/files/peboxaximanimagaloxezejo.pdfIn PDF document text
    • http://muabannhagiare.net/images/uploads/files/migadelejukelogudaxis.pdfIn PDF document text
    • http://tnshoppingbag.com/upfiles/file/guwepevi.pdfIn PDF document text
    • http://vipnovini.bg/root/f/uploads/files/36118703439.pdfIn PDF document text
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/e7f67025d6d80e841fb5fbd918193b16/filegisurinixi.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/91cdf5079efeadabe10a33b6734463b4/40474695679.pdfIn PDF document text
    • http://turchifiltri.com/userfiles/files/fejokitibegofenopaf.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139d944c3f02---sowibedusudumepuwa.pdfIn PDF document text
    • https://goez1.com/10005001208290177/ckfinder/userfiles/files/wedolafafebolanemezum.pdfIn PDF document text
    • http://grafiport.com/userfiles/file/8372966320.pdfIn PDF document text
    • https://footballsod.com/images/ck-uploads/files/pijosusopa.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_off0000d67b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD67B 10960 bytes
SHA-256: 93eaebd4bd7e2a7a0acfb357d2c2ec20b8803da7c7d8ba9abf528367dc10d481
font_01_sfnt_off0000efb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFB3 18548 bytes
SHA-256: eef7bd7292d5d53edc85b501a8cbe0c215d86cff4865df2f23e3dea2a7ed142e
font_02_sfnt_off00011e4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E4F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1