Malicious PDF — malware analysis report

Static analysis result for SHA-256 1136d658b43a468b…

MALICIOUS

PDF

95.8 KB Created: 2021-09-18 12:59:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f33067794c2f309edf9533de187dd5bb SHA-1: 43b029ec64bc674609b91e7edbb44d49a383c055 SHA-256: 1136d658b43a468bdadce878c48a36298a2b56487aef56aa26dc311e6d1315d2
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by multiple heuristics and ClamAV as malicious, specifically indicating phishing and trojan activity. It contains numerous external URIs, many of which are hosted on disposable domains, suggesting a link farm or redirection scheme. The ML classifier also strongly indicated maliciousness. While no scripts were explicitly extracted, the PDF structure and embedded URIs point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9888

Heuristics 5

  • 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.
  • 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://philabc.ru/uplcv?utm_term=how+to+download+podcast+on+android PDF link annotation
    • https://aayams.com/userfiles/file/53921280940.pdfIn PDF document text
    • http://th-hl.com///upload/files/xiberewosetivanutex.pdfIn PDF document text
    • http://stavebnevyrobky.sk/www/upload/files/2293331699.pdfIn PDF document text
    • https://demetraproject.eu/ckfinder/userfiles/files/nulagazivomipar.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/eb468256aee94e7145d7c27918507332/muzida.pdfIn PDF document text
    • http://mrrb.nexgendevgroup.com/files/78407860226.pdfIn PDF document text
    • http://modern-pro.ru/files/file/kizizudokumanagewulejeze.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/48940218298.pdfIn PDF document text
    • https://gujaratisamajparis.org/upload/files/7749527917.pdfIn PDF document text
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/2b2975a24a30e0da51054d1e02845c5b/32181628640.pdfIn PDF document text
    • https://yk-tech.com.tw/ckfinder/uploads/ckfiles/files/vopasuxokumu.pdfIn PDF document text
    • http://kalmi.ru/upfiles/files/82891810780.pdfIn PDF document text
    • http://seattlebestteriyaki.com/uploads/files/dirigejinalexegomojoli.pdfIn PDF document text
    • http://anm-av.de/uploads/files/60285586087.pdfIn PDF document text
    • http://webinaris.eu/ckfinder/userfiles/publics/files/rusuninezezamazugemo.pdfIn PDF document text
    • http://energyexcess.com/userfiles/file/vololunomojepumu.pdfIn PDF document text
    • http://jyy.jp/ckfinder/userfiles/files/20210918_124802.pdfIn PDF document text
    • http://freewest.at/67755912995.pdfIn PDF document text
    • http://domosplast.hu/files/file/2846259458.pdfIn PDF document text
    • http://travel-door.com/userfiles/file/60850229910.pdfIn PDF document text
    • http://peak-experience-europe.com/images/blog/file/jagupamoriru.pdfIn PDF document text
    • http://candientushinko.com/images/file/16455344885.pdfIn PDF document text
    • https://avela.md/userfiles/file/dazetaxufegapudagusev.pdfIn PDF document text
    • http://megat.pl/uploaded/fck_files/file/61614068110.pdfIn PDF document text
    • http://snnet.kr/board_pds/fckeditor/2021/09/file/suriz.pdfIn PDF document text
    • https://cristalparkhotel.com.ve/ckfinder/userfiles/files/66695437968.pdfIn PDF document text
    • 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_off00011176.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11176 18352 bytes
SHA-256: 63f0f2c3d119bff7870a4b83013778bc3f036b9fcf31dcc96d8f4a773fd32ee6
font_01_sfnt_off00014150.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14150 10452 bytes
SHA-256: 5259d43cdcb778ac6a66c8424416c4d2603b7c4f9adcab4036e35542c1d40258
font_02_sfnt_off00015924.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15924 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1