Malicious PDF — malware analysis report

Static analysis result for SHA-256 853e64fa26c5d2b3…

MALICIOUS

PDF

81.8 KB Created: 2021-09-13 19:03:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 050f51feb2edc2ec55a5f922466fff50 SHA-1: fb161c72db68f529c162ffd2e77c002b55db51aa SHA-256: 853e64fa26c5d2b3b6faaf184d82ac720a0ae09e8e45bdfb6bfa71fe038e2663
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to PDF files hosted on compromised websites. This behavior is indicative of a link farm designed to redirect users to malicious content, likely for phishing or to download further malware. The ClamAV detection and ML classifier strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://chcial.ru/uplcv?utm_term=stuck+in+the+mud+game+rules PDF link annotation
    • http://goodfortune.hk/UpLoadFile/file///masitegetewenifel.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/edf893fbe7408841a8ef8b192fca79a2/77507608511.pdfIn PDF document text
    • http://argyleliquidations.com/userfiles/files/zabaxexutokitez.pdfIn PDF document text
    • http://m2m2design.com/userfiles/90459439420.pdfIn PDF document text
    • http://max-metal.pl/gfx/file/jovenido.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613da7cd57948---miban.pdfIn PDF document text
    • https://elearning-chemistry.ro/userfiles/file/26379745462.pdfIn PDF document text
    • http://www.mariabeckmann.com/fotos/uploads/files/53874324964.pdfIn PDF document text
    • http://machinesupplier.cn/data/product/file/202192_6626_820.pdfIn PDF document text
    • https://it-remarketing.pl/app/webroot/media/files/zawilipelikekamox.pdfIn PDF document text
    • http://kbfrutos.sk/images/_file/kokafobazokivatesapazinuz.pdfIn PDF document text
    • http://wm-meyer.de/meyer/admin/editor/ckfinder/userfiles/files/58495440952.pdfIn PDF document text
    • http://cngwalk.com/fckeditor/userfiles/image/vebod.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613271948083f---22324939710.pdfIn PDF document text
    • http://livestreaming.group/wp-content/plugins/super-forms/uploads/php/files/53bl9n977u2ph9dqi1k2b3k6klm7fik5/86506497332.pdfIn PDF document text
    • http://ephtour.com/FileData/ckfinder/files/20210905_DF5CE1EA83565006.pdfIn PDF document text
    • http://fluorescent-training.com/file/borebajeritapav.pdfIn PDF document text
    • https://dammesliepas.lv/ckfinder/userfiles/files/salojuxokajapupatesabupu.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/d7d5c8ffc31bb696f3fbaa0fd36374ab/fusikabutoremekepu.pdfIn PDF document text
    • https://franchiseharbor.com/files/files/jelowa.pdfIn PDF document text
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/dq3c1bnm035nl37mklv2tfimvm/45657330462.pdfIn PDF document text
    • http://stadtbild-intervention.de/Quansis/ckfinder/userfiles/files/sexisanasavutamowika.pdfIn PDF document text
    • 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_off0000d919.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD919 10964 bytes
SHA-256: 8af9076622bb935c0eca324d420fdfb0cc0aedc0696dbb249defc6568a2e80dd
font_01_sfnt_off0000f21d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF21D 18400 bytes
SHA-256: 649a42aa02d9bab93d655a371228fbb4ac0324a4ab504c7553c5c583b94541c6
font_02_sfnt_off0001222d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1222D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1