Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c935aff4a364135…

MALICIOUS

PDF

85.7 KB Created: 2021-09-17 20:25:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 7973bf22d448e3630a7feb58c8491ddb SHA-1: 5735da41dcf25e81b49b26c30711516b5d4abc26 SHA-256: 9c935aff4a364135898a0d2752385e484745f4dfa443d9e0b378831412190841
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, and it contains embedded JavaScript. It also functions as a link farm, directing users to numerous external PDF files hosted on disposable domains, suggesting a phishing or malware distribution campaign. The presence of embedded JavaScript indicates an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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
  • 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://nomylo.ru/uplcv?utm_term=best+ux+android+apps PDF link annotation
    • http://hasadtemizlik.com/upload/file/sapilagokojaf.pdfIn PDF document text
    • http://universalestetic.com/userfiles/file/94574625641.pdfIn PDF document text
    • http://beloezoloto.ru/userfiles/file/87897518542.pdfIn PDF document text
    • http://polins.org/public/userfiles/file/13196726236.pdfIn PDF document text
    • http://eventclub.pl/userfiles/file/77520803158.pdfIn PDF document text
    • http://piemonteforyou.it/userfiles/file/gudanowukapukuzon.pdfIn PDF document text
    • https://pelletier-tp.fr/ckfinder/userfiles/files/50868912600.pdfIn PDF document text
    • http://dalieuht.com/app/webroot/uploads/files/34594539482.pdfIn PDF document text
    • https://acp-luxusingatlanok.hu/ckfinder/userfiles/files/2517539857.pdfIn PDF document text
    • https://simpangkanan.com/contents/files/mizilagupudubomab.pdfIn PDF document text
    • https://aiaciran.org/cache/fck_files/file/84503187772.pdfIn PDF document text
    • https://ecohort.biz/userfiles/files/56677628487.pdfIn PDF document text
    • https://clubslotalmatriche.com/calcas/file/10180330542.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/a8347df4b3af84d14da00aa3c1075882/84299087808.pdfIn PDF document text
    • http://snft.ro/media/file/libadipavejalewud.pdfIn PDF document text
    • https://serpavenger.com/ckfinder/userfiles/files/18746974935.pdfIn PDF document text
    • http://donaldnathanlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/15751252885.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/161422778b34d6---78641661910.pdfIn PDF document text
    • http://hatdesechia.com/storage/ckfinder/files/gikido.pdfIn PDF document text
    • https://cabsfromheathrow.com/userfiles/file/fotufubefufukozazaniguga.pdfIn PDF document text
    • https://www.caissedesecolesdu5eme.fr/backoffice/ckfinder/userfiles/files/63165826484.pdfIn PDF document text
    • https://moraure.net/js/ckfinder/userfiles/files/pipigizizen.pdfIn PDF document text
    • https://austarpharma.austarchina.com/upload/files/71695815622.pdfIn PDF document text
    • http://autolubitel-irk.ru/userfiles/file/lowetujuxil.pdfIn PDF document text
    • http://qunjl.com/userfiles/files/48218869791.pdfIn PDF document text
    • http://dalieuht.com/app/webroot/uploads/files/48763561668.pdfIn PDF document text
    • https://tpk-m.ru/files/file/fitivefepopu.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_off0000e970.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE970 18532 bytes
SHA-256: eee4a95ad941ccb0fef2ef079e769f28b8e70200f4ecefdc8faee6f301daa3f4
font_01_sfnt_off00011923.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11923 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001313a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1313A 10592 bytes
SHA-256: adff46996d72ee003970d4706dae4e11639ee8b13788240f5b43b6351e215f1f