Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb4a2b40147e603a…

MALICIOUS

PDF

72.6 KB Created: 2021-09-16 12:24:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: f2f3cdc3b0ae551c1b43948a63b7f9c9 SHA-1: 21e96e9394d168edd3076b487df637514bee6d67 SHA-256: bb4a2b40147e603a6be0431a52490408ef3f51af3db1643924e054e43acc48af
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, a common technique for exploiting PDF vulnerabilities or redirecting users. The PDF also functions as a link farm, with numerous external URIs pointing to various domains, some of which appear to be disposable or used for hosting potentially malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://xn--80aab8aioy.xn--p1ai/userfiles/file/gemojisokasasume.pdf In PDF document text
    • http://mehmetrasimmutlu.com/icerik/file/66481864319.pdfIn PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/44b89d1e7196b74bab9b3cbef05528c4/ridejabaditoxuvozurugexot.pdfIn PDF document text
    • https://xn--p3t29jo1ed4o4xw.tw/upload/files/62297908119.pdfIn PDF document text
    • https://www.willmarareachamber.com/ckfinder/userfiles/files/44408218622.pdfIn PDF document text
    • http://rioairporttransfer.com/ckfinder/userfiles/files/68229785658.pdfIn PDF document text
    • https://htchninc.com/d/files/61452248843.pdfIn PDF document text
    • http://krakow4you.pl/krakow/files/16953793206.pdfIn PDF document text
    • https://villatoscana-pi.it/userfiles/file/6898238806.pdfIn PDF document text
    • http://uktohabbarijamalta.com/files/file/bavekepipiferi.pdfIn PDF document text
    • http://openendrep.com/userfiles/files/4471335791.pdfIn PDF document text
    • http://snailgame.ru/upload/files/20210910224925.pdfIn PDF document text
    • https://biorenta.lt/ckfinder/userfiles/files/85001039420.pdfIn PDF document text
    • http://hauptlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/70777682937.pdfIn PDF document text
    • https://metnar.pl/web/uploads/files/sunopapuroz.pdfIn PDF document text
    • https://ph2020.org/ckfinder/userfiles/files/kexinu.pdfIn PDF document text
    • http://phuquytravel.com/nguyenvanlinh/files/487081827.pdfIn PDF document text
    • https://heuresromantiques.com/upload/files/8804253659.pdfIn PDF document text
    • http://toptoptraining.ru/img/upload/file/91752145060.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/18a0b9b2e4f07d772765ddaa5fcbc3b6/zebukofunikadowilewolon.pdfIn PDF document text
    • https://newchat.xyz/js/ckfinder/userfiles/files/23932404604.pdfIn PDF document text
    • http://wasserentkalkung.at/ckfinder/userfiles/files/65991199223.pdfIn PDF document text
    • https://uleshuzatabc.hu/files/file/nesigenizure.pdfIn PDF document text
    • https://unosms.us/userfiles/file/gilenug.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=friday+night+funkin+week+7+download+android+apkPDF 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_off0000b9fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9FA 16032 bytes
SHA-256: 10d27c5063d4bdb5ecf9bed146184c4a2df6876c10ba6eec944841929ff69a9e
font_01_sfnt_off0000e33d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE33D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fb54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB54 11028 bytes
SHA-256: e5d6d2bfaaeff465e9836f913f262a066a53b9fd9d16d1a633de3d729cd6b94e