Malicious PDF — malware analysis report

Static analysis result for SHA-256 33b443eba7852cb2…

MALICIOUS

PDF

90.5 KB Created: 2021-07-10 06:31:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b6609de1dfeb54f129f461d15e82f6cd SHA-1: 8877e73aa10127ec01d219db25aee1ec6f6427d6 SHA-256: 33b443eba7852cb21c485b980dfeacae9a245dbc2a445c738fdb26f00a6ddfaf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to numerous compromised WordPress sites, which in turn host other PDFs. This suggests a phishing or malware distribution campaign where the initial PDF serves as a lure to further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://techson-cctv.com/upload/file/remifojowekizupu.pdf
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a7840ce9121---47214862956.pdf
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/635ocqbsfcai69dtpm3jpqjs5n/nosir.pdf
    • https://www.m2asolutions.com/wp-content/plugins/super-forms/uploads/php/files/95671ab67dd8aabb5fdf1683a2fb7f65/20143675113.pdf
    • http://danguykhoidoanhnghiephp.vn/Upload/files/tajawamadivesarax.pdf
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9ec789736---suzitiraxasatawimokono.pdf
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/ftqf6bl26jvt5t5kh90o9lohi6/59496882050.pdf
    • https://menlopark.com/wysiwygfiles/file/31614775213.pdf
    • https://makenie.com/upload/files/18759260382.pdf
    • http://cravaluos.com/ckfinder/userfiles/files/nuvezoxobiwajiduv.pdf
    • http://fullcolorspandoeken.nl/userfiles/file/zesiserajeritum.pdf
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a66e0605882---28909324814.pdf
    • http://asianmosaicnyc.com/userfiles/file/jugufok.pdf
    • http://lexen.ca/userfiles/files/45811114460.pdf
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085af2954d2b---vebuxezijuvekotapofowuro.pdf
    • http://aiswaryamatrimonials.com/fck_uploads/file/30228716786.pdf
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/4991be47844f9b84155589a8d19f1304/kisurupe.pdf
    • https://edoxmarketing.com/wp-content/plugins/super-forms/uploads/php/files/qs3k75bcr0alu9lg6msbehqj9h/gigesawedolunuweboja.pdf
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c85d9047d8---jevodidefov.pdf
    • http://overtonnation.com/clients/f/f9/f97855507a39dfa58978186db9bff07a/File/migozetesevemujazivojodow.pdf
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608000b75b870---80757925373.pdf
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d734544241---28380004970.pdf
    • http://summithighschool1958.com/clients/71652/File/sewetogobi.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=dnd+sorcery+points
    • 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_off0001020a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1020A 16792 bytes
font_01_sfnt_off00011a21.bin
e2dac29949a5bd455747d2d29ba88a71f2b3038323bda152d9edc5a1ec1e6fc9
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A21 10416 bytes
font_02_sfnt_off000131d9.bin
02c67765f977939f54b2b74e76d6311b7ded8c828d0327a33e526e7a3a087a62
pdf-font-stream PDF embedded font (sfnt) at offset 0x131D9 16664 bytes