Malicious PDF — malware analysis report

Static analysis result for SHA-256 53a37124d8ebcda6…

MALICIOUS

PDF

87.3 KB Created: 2021-06-29 05:50:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5364022ca84c6e6b98ba0ad981e12765 SHA-1: 6c5b4351e97ced18e2f3738e5462b8af699edcae SHA-256: 53a37124d8ebcda6b8d77011772528ab685a0c8b819006df694e36c80eff9ded
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the analysis relies on the URL heuristics and AV detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://huntic.ru/uplcv?utm_term=shakespeare+in+love+nominations
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/d546ef3ea0d6a7b7c37a4312bd34579f/66961191701.pdf
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d55b212f7e---kupabukotuwize.pdf
    • https://www.mnspineandsport.com/wp-content/plugins/super-forms/uploads/php/files/70ed95b45859621b19e5ab9e73ea1e35/62645483689.pdf
    • http://adamlegal.com/userfiles/file/tefifunavi.pdf
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/852f51ba4c982c44b6f48d3b697741b8/lijinubadegudag.pdf
    • http://www.kickcommerce.com/userfiles/file/85440684039.pdf
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/uli995sactcr2cp2p8u8jroei7/xorotiforivatufol.pdf
    • http://tfh-filter.hu/_user/file/66628763558.pdf
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/4fa0f98da244846808b4e7c8dab93028/vamemalipemi.pdf
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f186853f7e---nevarebijotixir.pdf
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/a21cbbca715c624fd08bfe44f63df1f6/15776881360.pdf
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca141726c9---18841824145.pdf
    • https://ankaratemizlikcim.com/depo/sayfaresim/file/85122999883.pdf
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/37b0aa2b35d02fc8db3f43f3882a2791/jusavuzapifu.pdf
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/ieg773gppg02liqhl24dn7b0s3/53462346762.pdf
    • https://geneolock.com/locktactyuma/userfiles/file/66679316442.pdf
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/16088ea2c279d6---2614052797.pdf
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/a547aafd818d0d5bcc4a7da1a0617735/dapakovuge.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/u0f7nem9eoovf999ulkkldikf3/kamolejub.pdf
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/fcf9454866e56f7697a88a7bad49d661/28850456774.pdf
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a4bafa4d8b---20423402437.pdf
    • https://brandonsmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/t0pns7gj5ci7slgvm3iu96d2d2/37394433477.pdf
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/ordkpglh4nrr2d6q4q8c68ov24/dagovujorixiletaramolinon.pdf
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/76c295fqt68fua4p0vdsabi14s/wazogujitika.pdf
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/noderopemulinonere.pdf
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ab7667ff50---sujedureli.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_off0000f376.bin
ae0d391268a2fdeef169fec8410d13751d46164f7cdde0b60869d60f78ce9218
pdf-font-stream PDF embedded font (sfnt) at offset 0xF376 16868 bytes
font_01_sfnt_off00011f4a.bin
2c150a42b6d937e60735ca5e00b474ba749cc5943f1a03ec751fba8de3b9346b
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F4A 10748 bytes
font_02_sfnt_off000137d4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x137D4 16792 bytes