Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e73ffef8a1e316d…

MALICIOUS

PDF

70.1 KB Created: 2021-09-27 17:03:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 025a2435b652d9c4fff52f1f13aaada0 SHA-1: 56759587e2b10ef713ede4d94e4b7e06b2823332 SHA-256: 8e73ffef8a1e316d4de4dae2ecf820e332e9775ce3c1562e2e4066020cc02920
156 Risk Score

Malware Insights

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

This PDF was flagged by a machine learning classifier and ClamAV as malicious, indicating it likely exploits a vulnerability or employs social engineering. The presence of numerous links to compromised CMS upload storage and disposable hosting suggests a phishing or malware distribution scheme. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://btsoft.vn/uploads/files/17008390399.pdf In PDF document text
    • http://xn--80aer5aza.xn--80aai5amepo3c7b7a.xn--p1ai/ckfinder/userfiles/files/6956422847.pdfIn PDF document text
    • https://tdfstore.it/file/ruboratugaxubigaxodi.pdfIn PDF document text
    • https://briljant-maleri.se/UserFiles/files/gunobevolotasiwex.pdfIn PDF document text
    • https://www.tocbirsen.org.tr/ckfinder/userfiles/files/50064979719.pdfIn PDF document text
    • https://vmwarts.com/ecovic/file/8097472231.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b76a90c894---kewakaz.pdfIn PDF document text
    • http://stnicholasway.com/userfiles/file/85604843800.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/c69089b209822383a8996a0b1eb281ca/25234244261.pdfIn PDF document text
    • https://clinicamanila.com/ckfinder/userfiles/files/20360067287.pdfIn PDF document text
    • http://parbatsamajjapan.com/img/files/files/47322041182.pdfIn PDF document text
    • http://alkanboya.com/files/file///tebane.pdfIn PDF document text
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/69530798252.pdfIn PDF document text
    • http://wmsone.com/eimages/file/vovisapetajesela.pdfIn PDF document text
    • http://stphilomenaonline.org/userfiles/file/71988702297.pdfIn PDF document text
    • https://chowdhurytourism.com/ckfinder/userfiles/files/xovekevojaziv.pdfIn PDF document text
    • http://ticaproduce.com/ckfinder/userfiles/files/xutosiluriremefadojapeki.pdfIn PDF document text
    • http://2478.ru/admin/ckfinder/userfiles/files/xobuwadunofiwedig.pdfIn PDF document text
    • http://kovospm.cz/fotky/file/rajokutovek.pdfIn PDF document text
    • http://learningkey.org/userfiles/32510195854.pdfIn PDF document text
    • http://bridgeonlaw.com/filespath/files/20210925083125.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/p8ao2bnq9u4t56rsn9c9mgsdu4/15757772190.pdfIn PDF document text
    • https://metnar.pl/web/uploads/files/dedigakefatomapimevuwud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=bus+games+2020+onlinePDF 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_off0000af43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF43 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c75a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC75A 10648 bytes
SHA-256: 09c4f4843e4e95f7a7db6a9c9dfd3fd83428bcf257abfd1e86fc593363931a7b
font_02_sfnt_off0000dfbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFBD 17216 bytes
SHA-256: 4b5287f22266305f41ab5a998c779df64c2678040f9b7343aa2bee6c42dafcba