Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c7b52123b8cc186…

MALICIOUS

PDF

81.5 KB Created: 2021-09-18 23:49:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 2bd7475f76b80bf5bd75c7ba91b99ed3 SHA-1: 1878b0d7883a88dd6195c02d9e74faecafc06cb8 SHA-256: 4c7b52123b8cc1862bb7735796956594c86f2a0b79a7fc4c3ae75f402550155a
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many hosted on disposable domains, indicating a malicious intent to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this is a link farm designed to host malicious content or facilitate phishing. The ML classifier and ClamAV detection further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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 http://ameshamagazine.com/js/upload/files/8056488908.pdf In PDF document text
    • https://ariconium.cz/webpagebuilder/ckfinder/userfiles/files/juzasimoter.pdfIn PDF document text
    • http://xn--b1agaa2anfqdp.xn--p1ai/ckfinder/userfiles/files/jelodotojejubumetagaza.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/16141675aaf2b1---nifigivuxilimawi.pdfIn PDF document text
    • http://ccshecea.org/upload/files/17243324036.pdfIn PDF document text
    • http://ciba.lv/uploaded/file/31227022110.pdfIn PDF document text
    • https://thebillionbottom.com/business_school/uploads/file/junutaxisimones.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/ulne87mp2nhb37vbvp4skn78tb/fokijeter.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/1058539742.pdfIn PDF document text
    • http://www.scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/28165952904.pdfIn PDF document text
    • http://www.hro.ait.ac.th/js/ckfinder/userfiles/files/pafolitar.pdfIn PDF document text
    • https://onthespothousing.com/userfiles/file/67645321490.pdfIn PDF document text
    • http://radio6deenero.com/uploaded/files/64881990241.pdfIn PDF document text
    • http://upoart.com/ckfinder/userfiles/files/vuwugagajibu.pdfIn PDF document text
    • https://vkgnassociates.com/dayafter/uploadimages/newsimages/file/bineke.pdfIn PDF document text
    • http://dribblebar.pl/userfiles/file/85259733737.pdfIn PDF document text
    • http://konikanarrowfab.com/ckfinder/userfiles/files/78042052201.pdfIn PDF document text
    • http://primeasset.hu/fileok/file/9225388863.pdfIn PDF document text
    • http://4yoga.by/pics/files/79377846905.pdfIn PDF document text
    • https://fullhousetourism.com/UploadFiles/file/20210902201012172.pdfIn PDF document text
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/fufakavunubosesexa.pdfIn PDF document text
    • http://bdsps.org/slbdavbatala/userfiles/file/bujivexizezosifudojosem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=uninstall+app+from+android+studioPDF 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_off0000d6f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6F2 10636 bytes
SHA-256: 2637851de50c909bc169263714e2fc39e4a0524faf167c7e6c4feced3fb6d070
font_01_sfnt_off0000ef37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF37 18600 bytes
SHA-256: acfa7365314218930eb715b4b56ecd4be045e4cfebefcc20d388f7463732d145
font_02_sfnt_off00011fbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FBE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1