Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a1924ec39bb9bac…

MALICIOUS

PDF

82.6 KB Created: 2021-09-21 01:52:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7db81b4b4993e8522eaec75552abe96f SHA-1: a42bb61532c8003dc7cae834bf2ad0ad48edbb25 SHA-256: 5a1924ec39bb9bac2f38c8e3c633f988225080cd87da8f0a470a748c0d6ff45e
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many of which point to compromised WordPress upload storage or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

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 http://venusland.vn/app/webroot/img/files/72961167213.pdf
    • https://atkarisuli.hu/userfiles/file/58621811328.pdf
    • https://nirkongrp.com/ckfinder/userfiles/files/benume.pdf
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/4e980ae07bdc5b545a82bab188b61666/59299301730.pdf
    • https://marblobaths.com/app/webroot/img/files/47056863989.pdf
    • https://blueparadise.pl/userfiles/file/mugadiwizaduzifixuvanezal.pdf
    • http://2013.letnifestiwal.pl/ckfinder/userfiles/files/84369918388.pdf
    • http://panda-es.tokyo/yamituki-n/uploads/files/87018072454.pdf
    • https://www.premiumtrade.ro/ckfinder/userfiles/files/666767046.pdf
    • http://talleresjpg.es/img/file/likepeluwamasorizizax.pdf
    • http://podushka.by/files/files/sogabuko.pdf
    • http://centromp.it/userfiles/files/nezizujemonadolujamuxaru.pdf
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cda43f390d---327113403.pdf
    • http://ibarugi.com/fckeditor/userfiles/file/40007533848.pdf
    • http://gzperson.com/uploadfile/files/60640585877.pdf
    • http://thuephotocopytaihanoi.com/upload/files/luzatiporatitepa.pdf
    • http://xn--80ahcjevtqq.xn--p1ai/ckfinder/userfiles/files/sivegisafalot.pdf
    • https://giasidaily.com/uploads/userfiles/file/3331437477.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cf263d3fb6---pefexebutajoxuzejik.pdf
    • https://ladida.asia/sporlegen/administrator/imagetempfile/mijakivotowejurododopesi.pdf
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613516ea77255---35737281877.pdf
    • http://topas.lt/userfiles/file/defibazak.pdf
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16147ffe21ed7a---dozim.pdf
    • http://tcsm62.org/uploads/news/file/fulatosinoku.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=mp3+bearbeiten+android
    • 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_off0000db87.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB87 16792 bytes
font_01_sfnt_off0000f39e.bin
f30c22a5ecd2869e40d77b3fd350438d1fe4eade6c6db6cd3eb96361539f238f
pdf-font-stream PDF embedded font (sfnt) at offset 0xF39E 10476 bytes
font_02_sfnt_off00010b4e.bin
f2c4da7818188fe36a46ffca7431a355d68969f5d2dd4750a6351036853764b0
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B4E 19424 bytes