Malicious PDF — malware analysis report

Static analysis result for SHA-256 87878b7ee38e1363…

MALICIOUS

PDF

83.0 KB Created: 2021-09-14 06:08:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 817e734002a79c2905efaf120ac3a4db SHA-1: 7f9862659b185837932781d69073464728b84fe4 SHA-256: 87878b7ee38e136377e66424305c803fe1e7c5b5a495f5a0e939f6bbb2fb68c0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://pixomot.ru/uplcv?utm_term=how+to+create+overlay+in+android PDF link annotation
    • http://xn--o39a91gvwm83kbsn.com/FileData/ckfinder/files/20210913_84009A609BB43E90.pdfIn PDF document text
    • http://debseven.net/UserFiles/File/tabuwebol.pdfIn PDF document text
    • http://marklaliberte.com/fckupload/file/makesuwoto.pdfIn PDF document text
    • http://jatyn.cn/upfiles/202109/file/1630776863.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/fdf9d95b489ee89b124d12b61214c461/bokomiguxeliwus.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/87232949314.pdfIn PDF document text
    • http://infinivideo.hu/sites/infinivideo/files/xobuna.pdfIn PDF document text
    • http://phanphoiongnhuahoasen.vn/upload/files/19765680217.pdfIn PDF document text
    • http://www.allatpatikapecs.hu/images/file/gabukenimanarabigoxeb.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161357dd80ea07---3451675459.pdfIn PDF document text
    • http://dlabiura.kbo.pl/ckfinder/userfiles/files/siwana.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613d4123b3561---22179002748.pdfIn PDF document text
    • https://chung-pei.com/userfiles/file/32774430239.pdfIn PDF document text
    • http://gr-chem.com/upload/files/sebulibadas.pdfIn PDF document text
    • http://ordineveterinarireggioemilia.it/userfiles/files/mamaxikupevetig.pdfIn PDF document text
    • https://prolocolidodisavio.org/ckfinder/userfiles/files/kuvenugewiwalenibizolu.pdfIn PDF document text
    • http://teplo76.ru/uploads/file/woxivibo.pdfIn PDF document text
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b571fc474f---4402161162.pdfIn PDF document text
    • https://ciela13.leaddeehub.com/userfiles/files/binananokifofatusulub.pdfIn PDF document text
    • https://xn--fiqa735be48e.com/upload/files/getinevisoxiroxogunivewi.pdfIn PDF document text
    • http://firewheels.pe/userfiles/file/pekujumifetezaxinu.pdfIn PDF document text
    • https://chulintemple.org/CKEdit/upload/files/34362080576.pdfIn PDF document text
    • https://hgqq.hk/tony/churchofgod/ckfinder/userfiles/files/53105221722.pdfIn PDF document text
    • http://balie.overeembv-profielen.nl/upload/files/16108804198.pdfIn PDF document text
    • http://greece-ex.com/images/blog/file/10780273681.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_off0000e33f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE33F 16736 bytes
SHA-256: 91c654c74809591f0d247259daafec15ffba5d0b29b6307c31cff103a722f796
font_01_sfnt_off00010e69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E69 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012680.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12680 10452 bytes
SHA-256: e5a80ab928da8ac748f6951f6b5f6fa7a434b199d25013e3ad92be0c165410c6