Malicious PDF — malware analysis report

Static analysis result for SHA-256 351916a1fedf34d6…

MALICIOUS

PDF

88.7 KB Created: 2021-08-29 10:51:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 547327873926e4797eafe650b72d09d7 SHA-1: a6ff7a76e866149a6a6e3467d53b7e6792f81ceb SHA-256: 351916a1fedf34d671f81618b04e469664620651102c9a82f837684cd71d0a4f
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and link farms pointing to compromised domains, indicating a phishing or redirection attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lead users to malicious content or phishing sites. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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=ecological+importance+of+sea+cucumber PDF link annotation
    • http://cec-intl.ru/app/webroot/files/file/zeguriwagasosididavoz.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/rpmsm2dpr2deahiupqgsv1q1u5/63138468904.pdfIn PDF document text
    • http://i-daa-wl.de/userfiles/82716112073.pdfIn PDF document text
    • https://bandotrading.com/uploads/file/ranelunifedojiwodulezi.pdfIn PDF document text
    • https://yar-net.ru/userfiles/file/2100033670.pdfIn PDF document text
    • https://tipresentoio.it/images/file/muxesa.pdfIn PDF document text
    • https://daquin-ferriere.fr/userfiles/file/jezapuvuzozemipire.pdfIn PDF document text
    • https://bjjewels.net/nbloom/fckuploads/file/xavaj.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/939345f5df4d54dff3992b4110f4f676/bomitekebapuxulelome.pdfIn PDF document text
    • http://thebeautyofdesign.nl/ckfinder/userfiles/files/zimejofotojorodaxexelider.pdfIn PDF document text
    • https://rpdev.org/ckfinder/userfiles/files/92693318996.pdfIn PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c54c2d127a8---80154923679.pdfIn PDF document text
    • https://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/0955b1d04103ad67a7580fc3d6460b97/60456525450.pdfIn PDF document text
    • http://quickvideo.nl/userfiles/file/30585769950.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071034b48e6d---dupodapadidexadozizepu.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/eq3ova96eikm90fejaakhefv1q/miwovazaxawevaruwuwibi.pdfIn PDF document text
    • http://writtenmail.com/upload_images/file/gekinorun.pdfIn PDF document text
    • http://yoron.net/up/files/raretupepevamasajisutilop.pdfIn PDF document text
    • http://karat-dobremiasto.pl/userfiles/file/64634854635.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c85fe0ee16---vefasosemavuv.pdfIn PDF document text
    • http://sipzip.com/userfiles/file/jexolowinaguvoxunidu.pdfIn PDF document text
    • https://skyzoan.com/cake/beta/userfiles/file/gisaxodulovogabeguk.pdfIn PDF document text
    • http://catherine-massage.com/ckfinder/userfiles/files/sapafumebubamixanigoma.pdfIn PDF document text
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f69a745365---danasozajekowozobepoxopop.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_off0000f1bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1BB 19696 bytes
SHA-256: 694311868d094e17e70d669be16c6ad634744282df2c2774a5eba858d25761fe
font_01_sfnt_off00012341.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12341 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013b58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B58 11044 bytes
SHA-256: dfd24457cdce1951b8d0d0614e73b860c0cd44bae095ca3d952c69617a6e0f93