Malicious PDF — malware analysis report

Static analysis result for SHA-256 33b1744f55e56125…

MALICIOUS

PDF

72.7 KB Created: 2021-09-24 21:04:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 238f151c0b2f2a98404539b380d22a45 SHA-1: 35ae81bd7611c5803da843a8ab47da03da634fb4 SHA-256: 33b1744f55e5612595f380e8f10289867cd37f09af15d9d51fff19878b9d488f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous external URIs and links to various domains, many of which are hosted on disposable or compromised hosting, suggesting a link farm designed to redirect users to malicious content. The presence of PDF-specific heuristics like 'PDF_URI' and 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this attack pattern.

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
  • 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 https://queure.ru/uplcv?utm_term=friv+bob+the+robber+4
    • http://geometramaurotozzi.it/userfiles/files/15885156615.pdf
    • http://softtox.com/new/userfiles/file/tikanisorumada.pdf
    • https://binarbaidequipment.com/public_html/userfiles/file/puraguwiri.pdf
    • https://vieclamlaocai.vn/webroot/img/files/75692309077.pdf
    • https://tanhaithanhvalves.com/quangcao/admin/file/7960174401.pdf
    • http://biancoacolori.it/userfiles/files/81254666978.pdf
    • http://jgbt.us/pds/userfiles/files/bokewanidusijunigiz.pdf
    • https://aicpwdosaeast.com/ckfinder/userfiles/files/depunavonuxutaraf.pdf
    • http://labsshop.com/d/files/lojomoluxataref.pdf
    • https://cochleartudaskozpont.hu/files/33239834475.pdf
    • http://okmarin.ru/userfiles/file/xanimakokogekixapu.pdf
    • http://phuongdonggolf.vn/app/webroot/uploads/files/15996254982.pdf
    • http://scandinavia-ex.com/images/blog/file/venavusokaj.pdf
    • http://yuanjiangchem.com/upload/files/80420470136.pdf
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fea9a4ca99---5666442283.pdf
    • https://maviet.vn/upload/files/70045375248.pdf
    • http://kpghomerepairs.com/uploads/image/files/lazizadagovisuvi.pdf
    • https://sport-jicin.cz/dokumenty/54240476052.pdf
    • http://byecook.com/ckupload/files/xozifakefe.pdf
    • https://tenshinorchids.com/FCKeditor_upload/file/bemerowusilu.pdf
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c1b03944f3---pojif.pdf
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/2537ecc4382483866c6c354c21e5f7cc/sukitad.pdf
    • https://verlauf-ekb.ru/admin/ckfinder/userfiles/files/popofozexevapu.pdf
    • http://optykglowacki.pl/obrazki/files/26393332385.pdf
    • 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_off0000b7fe.bin
0e08881b261baad636582f78e45f3ddce8bb5f6a354f9a33bab2a423743ac1af
pdf-font-stream PDF embedded font (sfnt) at offset 0xB7FE 9988 bytes
font_01_sfnt_off0000ce4c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE4C 16792 bytes
font_02_sfnt_off0000e65e.bin
76193a229d68b093afe038655cb5f2768a1f734aafeff917689a50889be31334
pdf-font-stream PDF embedded font (sfnt) at offset 0xE65E 18396 bytes