Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f0011f2162fc72f…

MALICIOUS

PDF

71.1 KB Created: 2021-09-28 06:03:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6da97c745bfbdfbd7543c2f653a02a54 SHA-1: 58ffd121ac977ecbbe9647abeef695e3e67a6931 SHA-256: 9f0011f2162fc72f89345c97d19b0bab72b6e8cd98b8b4202480cbbaa3def9db
96 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to disposable hosting, a common tactic for distributing malware or phishing content. The ML classifier strongly indicated maliciousness, and the presence of multiple PDF link farm heuristics further supports this. The document body is heavily obfuscated and unreadable, providing no direct clues about its specific purpose beyond the link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

Heuristics 5

  • 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://dobski.pl/userfiles/file/32485475257.pdf In PDF document text
    • http://oroblupiscine.it/userfiles/files/gaxofekidetonamebuwavudu.pdfIn PDF document text
    • http://inkjetartandimage.com/Uploads/file/nolozakekutikujagikana.pdfIn PDF document text
    • http://unesco-mediain.cz/fckfiles/file/rugusedilok.pdfIn PDF document text
    • https://newegys.egyseg.eu/ckfinder/userfiles/files/liputobaliki.pdfIn PDF document text
    • http://mesterteto.hu/userfiles/file/tatumerovuda.pdfIn PDF document text
    • http://eros-arena.de/eros/userfiles/file/97950378457.pdfIn PDF document text
    • http://avtrak.ru/ckfinder/userfiles/files/59947703538.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/03d8d294908d2fa83f17d6b75c34bd69/17922148643.pdfIn PDF document text
    • http://palami.by/images/file/44808479497.pdfIn PDF document text
    • http://eia-edu.com/userfiles/file/digel.pdfIn PDF document text
    • http://reclameindex.nl/images/uploads/gelaxasezefejus.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec285ee348---10064893885.pdfIn PDF document text
    • https://glamweddingdesign.com/userfiles/file/tamoresolanekawo.pdfIn PDF document text
    • https://comfortinnbarrie.com/phpsites/vertical_living/uploads/file/19422152911.pdfIn PDF document text
    • http://thegoshow.net/userfiles/file/46774928304.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/livomuxutadofug.pdfIn PDF document text
    • http://t-p-fortune.com/userfiles/file/52995399571.pdfIn PDF document text
    • http://anapro.com/ckfinder/userfiles/files/gutowelekejivox.pdfIn PDF document text
    • http://cu-mbc.com/ckfinder/userfiles/files/69496893823.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/e6c5fdf7ddf97cb35e99aa371eaad52c/pifanatagajalizij.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/3uj7lsgkr1p2qsni0btpq85igk/magixiwonupi.pdfIn PDF document text
    • http://orvosvalaszto.hu/uploads/files/xikatiwodelikemilugebu.pdfIn PDF document text
    • https://dyaa.club/uploads/file/vamozitijoke.pdfIn PDF document text
    • https://harom.ro/files/file/nafuwiseza.pdfIn PDF document text
    • http://vibratingsieve.com/d/files/17208054284.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=apk+of+robloxPDF 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_off0000b510.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB510 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD26 9908 bytes
SHA-256: 282fe46f853bdbf3a3884ecb7d926410d4dce4d0bf953ac09bc798632625ecb7
font_02_sfnt_off0000e2dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2DC 17640 bytes
SHA-256: f465b165ad09fead0e564f595b08b0f1af9867e15bff53e8c50edc15bb5924a8