Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6b83d345edbf75d…

MALICIOUS

PDF

99.7 KB Created: 2021-07-25 16:41:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: faec0c85c05b943b1460f16194b0568c SHA-1: 9673a7dfda0d82b7bc15500b72e9e6162d452faf SHA-256: b6b83d345edbf75d74a76d0fdc66f433c37399ff572db6d061778b7f588020ee
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. These links likely serve as a distribution mechanism for further malicious content or phishing attempts, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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 http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c43d33c5a86---45340258977.pdf In PDF document text
    • http://kme-kme.cz/files/file/wapuzosi.pdfIn PDF document text
    • http://svb-volleyball.de/userfiles/file/41405419299.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/sooki09jfdsgmffff34c47qsk4/71138400094.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160ca21b01caa3---42466925525.pdfIn PDF document text
    • http://jinxinghotel.com/uploads/files/wexokasumugiganekujuxobu.pdfIn PDF document text
    • https://best-label.com/upload/files/24625380980.pdfIn PDF document text
    • http://hopkinshigh1966.com/clients/1/10/1054c114374c88b4a165e91103565d41/File/xafalurolanemusenuruzafa.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdbafd766f8---vofokokebonodifesajiwuze.pdfIn PDF document text
    • http://adams-gold.ru/archive/image/file/danesoz.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/ac097c4a07cbf18a8b2f926772a8db95/28284048787.pdfIn PDF document text
    • https://bodwellassociates.com/wp-content/plugins/super-forms/uploads/php/files/2e0281f5782ca6ddd8ba8a72c0e0ff34/1113754443.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a30bff1fba2---24597210707.pdfIn PDF document text
    • http://transbur.ru/admin/ckfinder/userfiles/files/ruxibetifotilijawabixoj.pdfIn PDF document text
    • http://ip-golubev.ru/ckfinder/userfiles/files/90575635634.pdfIn PDF document text
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/jowigo.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160762f239d611---55412068924.pdfIn PDF document text
    • https://botorka.ro/userfiles/file/65339460376.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/4c06b49d0a485726cfee8e9a4f7b4997/24758790109.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b5fe5536a29---25399461897.pdfIn PDF document text
    • https://www.bussmann-tiefbau.de/ckfinder/userfiles/files/bedifinutilode.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607407ff17d9f---50551765139.pdfIn PDF document text
    • http://facilitymanagementassociates.com/survey/userfiles/files/49432499360.pdfIn PDF document text
    • https://jfefood.com/wp-content/plugins/super-forms/uploads/php/files/ecad59a783b88da748ed129a80235f84/rubimunepikafekomini.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=causas+de+trombosis+venosa+profunda+en+miembros+inferioresPDF 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_off00011c8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C8E 10952 bytes
SHA-256: bf83cd4f3122ad37ebcd0f0ba4532feba3c9886b09aa24a90dd7f449c197cdc4
font_01_sfnt_off000135c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014dd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14DD7 19160 bytes
SHA-256: 494c17e843454f21b03dd09f4550e56863b8965f2a203e87f16c91b5de506333