Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4c6e9e0ba080ebd…

MALICIOUS

PDF

87.5 KB Created: 2021-09-08 08:48:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 88ce92b9dbd27816c4685043a41313d2 SHA-1: a062e9c928d2d0c03fe5de3cdb708dc2d8a7e5b7 SHA-256: a4c6e9e0ba080ebdd43f538fa0ef11f7827020ef10f69641728674bf3de9ec40
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains a large number of external URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting it functions as a link farm to distribute malicious content or conduct phishing attacks. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://philabc.ru/uplcv?utm_term=hazardous+waste+disposal+methods+pdf
    • https://holyfamilyhospitals.com/ckfinder/userfiles/files/80608315526.pdf
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adce546e28d---43687819020.pdf
    • http://amsaneeraus.fi/userfiles/files/95333185147.pdf
    • https://legyenegyjonapod.hu/userfiles/files/xupilafegakevipafitumivo.pdf
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/6e1eb3ab26bebca9a79b98e927986718/32407211290.pdf
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/ae9c4671fc11948418d1573866c7f324/63914845971.pdf
    • http://ayhancevik.com/images_upload/files/pufuratirex.pdf
    • http://ingenermarket.ru/userfiles/50039680707.pdf
    • http://artecgroupservices.com/imagenes/file/vowaluvijubosewaraponegud.pdf
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b968d35e8c6---63636623555.pdf
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/160711edb35fc1---48839972619.pdf
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d651a4a9d49---govivogegajumitokomejujom.pdf
    • http://villabrown.it/userfiles/files/97202810810.pdf
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1611362fbbcada---33478836935.pdf
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9387368ff0---60542036743.pdf
    • https://roweryelectra.pl/app/webroot/uploads/file/16245883751185.pdf
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/750cc8e9bfa1705311dd207b2da3d598/getifojuwunenisipe.pdf
    • http://netcentricnj.com/ckfinder/userfiles/files/fizutujiruxivupexeluvatex.pdf
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/j08ptje9o7bael8l4nrrq28icu/26632146383.pdf
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e3b3d08a4f---wumiwopabopisuvawana.pdf
    • https://korovin.org/site/img_ufiles/kajikewotutifu.pdf
    • http://sladkiy-ostrov.ru/userfiles/files/42573166212.pdf
    • http://langeline.com/ckeditor/upload/files/43124074348.pdf
    • http://pkynfe.net/userfiles/file/xadezekutesefixezuja.pdf
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b49618c9a96---36265046456.pdf
    • 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_off0000ee17.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE17 16792 bytes
font_01_sfnt_off0001062e.bin
0e09aa19702506bf4268640bd578674d8ae5e9707f3c8bd3e2701801eecd7eea
pdf-font-stream PDF embedded font (sfnt) at offset 0x1062E 10896 bytes
font_02_sfnt_off00011f6a.bin
dc8816f74b14a5dfe3c58725fcc6e5e02b44c81e29ed684114ba371e5fc75b78
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F6A 19140 bytes