Malicious PDF — malware analysis report

Static analysis result for SHA-256 b62a406fd4078d93…

MALICIOUS

PDF

71.0 KB Created: 2021-09-25 07:09:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 9e0937e7ca49c36a3281b3ae65aee45e SHA-1: 840008ab006161e94c116df0233b180b13bf8466 SHA-256: b62a406fd4078d93588e2f0d83af732c3e2c1d31a6bdf2694e94b2e293632b6a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as malicious by ClamAV and an ML classifier, and contains numerous embedded URLs. Several heuristics indicate it functions as a link farm, with some links pointing to compromised CMS uploads and others on disposable hosting, suggesting an attempt to obscure the final destination. The presence of external URIs and link farm characteristics points towards a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://securitydm.rs/slicice/file/xedafaji.pdf In PDF document text
    • https://ooo-kenk.ru/userfiles/file/wefupisaxavefukitafanelil.pdfIn PDF document text
    • http://robbes.nl/media/files/40324593006.pdfIn PDF document text
    • https://masterjobintl.com/ckfinder/userfiles/files/tuwul.pdfIn PDF document text
    • http://marcobernini.it/userfiles/files/38315157776.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614ae17703e46---pulotubawekatovo.pdfIn PDF document text
    • https://drproperty.in/userfiles/file/28182117430.pdfIn PDF document text
    • https://tatvan.in/userfiles/file/51800964129.pdfIn PDF document text
    • http://heninrealty.com/userfiles/files/46807455826.pdfIn PDF document text
    • http://areaengineeringsrl.eu/userfiles/files/mosisas.pdfIn PDF document text
    • http://wx-test.com/upload/ckimg/files/202109131310407052.pdfIn PDF document text
    • http://zhuoxinlaw.com/userfiles/file/20210914114840_480882229.pdfIn PDF document text
    • http://e-pisanie-prac.pl/famprojekt_z_serwera/images/file/bitupunutalibarutazo.pdfIn PDF document text
    • https://shipnhanh247.vn/asset/files/nifugobikuxo.pdfIn PDF document text
    • http://fleshlight-tw.com/userfiles/file/10284872929.pdfIn PDF document text
    • http://www.skk.com.hk/admin/ckfinder/userfiles/files/1386333117.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/2fcfc06627d3d164d79d00b9702f17fa/vevuzebomikizixore.pdfIn PDF document text
    • https://ascend.sut.ac.th/ce/2017/src/plugins/ckfinder/userfiles/files/tupuwekedogoti.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613e753f8c45a---xonuwetirisewigukawosuji.pdfIn PDF document text
    • http://pcserviszlin.cz/ckfinder/userfiles/files/bedugagos.pdfIn PDF document text
    • http://nail-free.com/ckfinder/userfiles/files/36242699992.pdfIn PDF document text
    • https://penzion-pod-rozhlednou.cz/img/file/412996179.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+bypass+lock+screen+on+iphone+7PDF 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_off0000b280.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB280 16520 bytes
SHA-256: 62e187ff33a560950fb9119a598d7d053aaebd6f93abf6e6f0e358fa03d55049
font_01_sfnt_off0000dcbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCBF 10944 bytes
SHA-256: 1f1776d449dc73c0c8add43e870b6bb5ade0aa2ab03fa23ac20d29c82e5effde
font_02_sfnt_off0000f5f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5F5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1