Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3967b16f42586cb…

MALICIOUS

PDF

70.7 KB Created: 2021-09-30 21:04:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: eca3c2a2183299afcbafa06c3b193d0e SHA-1: a7fe0dfb6ac953035549c0ecb4a14676f9649dd6 SHA-256: e3967b16f42586cb4d3bc14aee44640e88e1a800b198fd4b35c617ff10b551c8
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely redirects to external URLs, as suggested by the PDF_URI heuristic, which are often used for phishing or to download further malicious payloads. The numerous external links also point to a link farm, a common tactic for obscuring malicious destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

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 http://cps-mbstu.edu.bd/app/webroot/js/ckfinder/userfiles/files/6228649073.pdf In PDF document text
    • https://zifu-tech.com/app/webroot/userfiles/files/birejukedotutizowufo.pdfIn PDF document text
    • http://tomaszskiba.com/userfiles/file/17400439094.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b58ab7a3b5---81048726058.pdfIn PDF document text
    • https://hgindustrial.eu/userfiles/files/jesapomapiboxawa.pdfIn PDF document text
    • http://hstairan.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/45009577535.pdfIn PDF document text
    • http://naim.naparts.com/images/fck/file/vibuwituwugifiguj.pdfIn PDF document text
    • http://trungtinjsc.vn/upload/FCK/file/rutanapubexane.pdfIn PDF document text
    • https://www.gurkhasfinance.com.np/ckfinder/userfiles/files/kaleko.pdfIn PDF document text
    • http://bbpcosmetics.com/admin/upFiles/2021-9/file/58140010137.pdfIn PDF document text
    • https://edu-mate.kr/_UploadFile/Images/file/70337705085.pdfIn PDF document text
    • https://tiemhoahaibara.com/data/dulieu/files/solifamab.pdfIn PDF document text
    • http://elcolono.net/userfiles/files/sosutafukekagogopopor.pdfIn PDF document text
    • http://rotarybrescello.it/userfiles/files/zekilinuxenimepu.pdfIn PDF document text
    • http://seoulgreeter.com/userData/board/file/14615384848.pdfIn PDF document text
    • http://architettoannalisatinelli.it/userfiles/files/77342214195.pdfIn PDF document text
    • http://e-park.es/img/uploads/files/sidosawujowi.pdfIn PDF document text
    • http://newo.ru/files/files/nukadawusazolize.pdfIn PDF document text
    • http://kammatrans.com/userfiles/files/3856303668.pdfIn PDF document text
    • http://annabarons.com/files/files/71315108980.pdfIn PDF document text
    • https://www.q-jin.ne.jp/ckfinder/userfiles/files/64683285853.pdfIn PDF document text
    • http://sea-cruise.ru/ckfinder/userfiles/files/vaxilugafakifotaxoligalir.pdfIn PDF document text
    • http://damutech.kz/upload/2021/09files/210918132038730374mjfo7.pdfIn PDF document text
    • https://smartcrm.cloud/upload/files/34802619263.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=solution+manual+for+mechanics+of+materials+10th+edition+by+hibbelerPDF 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_off0000af84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF84 11344 bytes
SHA-256: 94e7b156beac5e0437ef25b099fe434e2c1af9fa78af51ff879def9e78a654de
font_01_sfnt_off0000ca07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA07 15884 bytes
SHA-256: 5eae681ae510b07424974acdc94c79be9eaf360c32350309fdc575593c39028e
font_02_sfnt_off0000f283.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF283 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1