Malicious PDF — malware analysis report

Static analysis result for SHA-256 3981c304dfa56c72…

MALICIOUS

PDF

86.7 KB Created: 2021-06-29 15:00:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 5bf443a50cb82c7dbde1ab30e4154cad SHA-1: 03048cbc46eb18ef76b9a5517e748e76fbefa4da SHA-256: 3981c304dfa56c72127f8919c97e185aaee1850f180beb54d5ab8e2b9e937990
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised CMS upload storage and disposable hosting, suggesting it functions as a link farm to distribute further malicious content. The presence of a 'download button' heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://cructi.ru/uplcv?utm_term=coherence+full+movie+download PDF link annotation
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/87ebbff334f7cd6bc80f47f61a259efc/63976932851.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac5603a3dd8---kogejato.pdfIn PDF document text
    • http://bbfederico2.net/userfiles/file/dixovikuzivevala.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b3e40d045---36661742134.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b3ce6dcba9---68186115677.pdfIn PDF document text
    • https://www.ltgpartners.com/wp-content/plugins/super-forms/uploads/php/files/591e02d1d10e7ad3a39a72028ce400d1/19280802640.pdfIn PDF document text
    • http://forter.vn/hinhanh/file/39089984373.pdfIn PDF document text
    • https://jfefood.com/wp-content/plugins/super-forms/uploads/php/files/38263759e50dbdc09d2ee9a669d627ae/nejutogovudefog.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072083136fad---26180256778.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c220580b9a8---penabiguzudakawiwus.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a3dc143aee4---43302429623.pdfIn PDF document text
    • https://invest.pl/userfiles/file/pukafasesipu.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0c8db2151d---53860495529.pdfIn PDF document text
    • https://beautyyaurient.com/editor_upload/file/96081559010.pdfIn PDF document text
    • https://nusamulticentralestari.com/Uploads/userfiles/files/xuvigilexe.pdfIn PDF document text
    • https://maxflowfans.com/userfiles/file/kuzipipofuvemakuvip.pdfIn PDF document text
    • http://stalmost.pl/userfiles/file/nazavupotirogizanarav.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/5ad0a139206967dee2432dfe313f04a8/35666900753.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1609c70c587a05---nekapotimurajixositu.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16080742b8e0ff---30672974713.pdfIn PDF document text
    • http://tizianaiberti.it/userfiles/files/lokuridi.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-5-14/20210514090139352919.pdfIn PDF document text
    • http://chanakyaaerospacedefence.com/userfiles/file/72577250662.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_off0000f0dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0DC 10760 bytes
SHA-256: 4a845fc811557339174be12f61c9bfa6aab665b86da5a6380691af296c2a56ef
font_01_sfnt_off00010973.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10973 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012185.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12185 16816 bytes
SHA-256: a1c5a4e878edee3a8b107cf384c9af0c043a53f8a56c639116b6dba78d8c1f4a