Malicious PDF — malware analysis report

Static analysis result for SHA-256 838c2e961cdf2af7…

MALICIOUS

PDF

70.7 KB Created: 2021-10-03 09:53:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 234749410ad8cb8018b0e5e2a0e94a0b SHA-1: 2e4bfb4c30b996ab133cc63339c1737afbf483f0 SHA-256: 838c2e961cdf2af7b0a4d2a9686e80d0f0bd45f9720af8abbb4d7327f636d05b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be disposable or compromised hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of creating numerous links on distinct hosts, suggesting an attempt to manipulate search engine rankings or distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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://garglob.ru/uplcv?utm_term=use+intercede+in+a+sentence
    • http://dissanna.com/temp/fckeditor/file/zivegowa.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/5dd2d40844bf8d4a9297cbd2b8fd0da2/teragugox.pdf
    • http://poliinc.com/upload/files/8850238883.pdf
    • http://antoniolescio.net/userfiles/files/vozuwasitopu.pdf
    • https://ikansambel.com/contents/files/nubuloletoruzop.pdf
    • http://crosswaysrecruitment.com/userfiles/file/vefezifafesapixetofogaro.pdf
    • https://communeouchamps.fr/userfiles/file/rivuruvusepat.pdf
    • http://omeofest.eu/userfiles/files/kozufemido.pdf
    • http://dmkaudit.sk/101/upload/file/20330043901.pdf
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161482f5076b27---pobewawulegefewut.pdf
    • http://www.lasallelille.com/admin/ckfinder/userfiles/files/ritenokabekuvunakugunomur.pdf
    • http://podhoru.cz/userfiles/file/56670549677.pdf
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/b0f4ece2f83619ac8cf885e7359878fd/sutop.pdf
    • https://obrbikes.com/files/files/zifoxosaxajonezamusedo.pdf
    • http://savvyais.com/userfiles/file/wuzevekiderexesos.pdf
    • https://olterus.info/contents/files/7134123454.pdf
    • http://opuspointpartners.com/ckfinder/userfiles/files/tagoxibakilaxan.pdf
    • https://mn-lawfirm.com/box/userfiles/file/bimibazadejiliw.pdf
    • http://laguna.piyawatgroup.com/images/files/folojerekawogupetuj.pdf
    • http://uralcomservis.ru/crn_fls/crn_files/wemozanexalekarofaje.pdf
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/b8rmgfbbvdl3lf8buqanodo9tc/kagipodofozevirin.pdf
    • https://carcarnet.com/home/sandbox/domains/hkdance.tritek.hk/public_html/ckfinder/userfiles/files/resexitupewi.pdf
    • http://tamker.hu/userfiles/file/70427367045.pdf
    • https://assignmentmart.com/ckfinder/userfiles/files/fuwovojosezodutepabu.pdf
    • http://hutnia.pl/userfiles/file/24574791298.pdf
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/161571a4409d1a---sozejinimojolakomebof.pdf
    • https://ichapps.com/ichapps/ckeditor-ckfinder-integration/uploads/files/21917098224.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_off0000b3ac.bin
8d7419b871bd4e32270c0275ff384382ea96805d1dfd9c2bade0e5fd13c5a66d
pdf-font-stream PDF embedded font (sfnt) at offset 0xB3AC 16656 bytes
font_01_sfnt_off0000de42.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE42 16792 bytes
font_02_sfnt_off0000f659.bin
6f96df80c453cd7cd7462b58f59806b566fffe85d9878cd60b1059130fc6d7a4
pdf-font-stream PDF embedded font (sfnt) at offset 0xF659 10204 bytes