Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4e8c413c6b2a616…

MALICIOUS

PDF

84.0 KB Created: 2021-08-17 17:55:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4bc784ab7f1aef6ef454500f970037b3 SHA-1: 88c00b8ad66bcbd0433aa912f06b6b1b850e7ed4 SHA-256: b4e8c413c6b2a616542836f24ed4dfcbe8056649754918da6c8adf91b488c028
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV heuristics strongly indicate this PDF is malicious, specifically flagged as a phishing trojan. The document contains numerous links to external websites, many hosted on compromised or disposable domains, suggesting a link farm designed to redirect users. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://www.pattyn360.com/upload/forum/files/zokifufowopebe.pdf In PDF document text
    • https://nffcd.org/userfiles/files/65199429925.pdfIn PDF document text
    • https://brazilairporttransfers.com/ckfinder/userfiles/files/bagojararamirep.pdfIn PDF document text
    • http://stadtbild-intervention.de/Quansis/ckfinder/userfiles/files/waloxabuxew.pdfIn PDF document text
    • https://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/398aa2f096fe8911ebf7c7f1770a73ed/notimuxijujobodanurupo.pdfIn PDF document text
    • https://goacetours.com/ckfinder/userfiles/files/57861431037.pdfIn PDF document text
    • https://sunpower.lv/ckfinder/userfiles/files/nabaditixigupoxelawizumef.pdfIn PDF document text
    • https://cbdc.co/uploads/ckfinder/userfiles/files/61879293570.pdfIn PDF document text
    • https://duproject.com/uploadEditor/files/gesisabodaxun.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1607b9f94cf078---32743605876.pdfIn PDF document text
    • http://cuacuonductudong.com/upload/files/83715573518.pdfIn PDF document text
    • https://daulte.com/ckfinder/userfiles/files/wigav.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/9f0d01bba2fa518711419814445611b4/retizafunomonekujasaw.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/51140752672.pdfIn PDF document text
    • https://tyeetomsfishing.com/userfiles/file/58720559848.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac12b473523---17894653362.pdfIn PDF document text
    • http://farmina.ru/uploads/files/negaju.pdfIn PDF document text
    • http://a-swiss.com/upload/userfiles/file/pibojixa.pdfIn PDF document text
    • http://aptchasers.com/FCKeditor/userfiles/file/nasedakutokidagup.pdfIn PDF document text
    • http://box8websites.com/ckfinder/userfiles/files/86294719197.pdfIn PDF document text
    • http://saltokisport.com/uploads/files/72337619071.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16097e73fda707---20491085312.pdfIn PDF document text
    • http://kahounova.cz/userfiles/file/37796191770.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/nudabofutevewobaje.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=happy+birthday+bible+verses+for+friendPDF link annotation
    • 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_off0000e533.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE533 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD4A 10904 bytes
SHA-256: f86fd285e3349721f6df808b0fa6e3b9c9123a1a39761595aed8e8626c951263
font_02_sfnt_off0001163b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1163B 17024 bytes
SHA-256: 439b5a0dc3c5dff765e5d930a1792b49361917d41e9b256828254df5c2b2f7e6