Malicious PDF — malware analysis report

Static analysis result for SHA-256 803b9b0d681772dd…

MALICIOUS

PDF

85.8 KB Created: 2021-07-02 06:54:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f14fb4a412fc81ac7282d0e217333f4b SHA-1: 2479efaa8ec21b2ab22569a6230c94201969ad34 SHA-256: 803b9b0d681772dd0517b3e9a2e07b81d6e7343d856ba3556e378d845316fb2d
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to various domains, many of which are hosted on compromised WordPress sites or disposable hosting, indicating a link farm designed to obscure the ultimate destination. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the presence of external URIs and the link farm pattern are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://oniceh.ru/uplcv?utm_term=free+nds+emulator+for+android
    • http://renovfab-menuiserie.com/userfiles/file/susekoxejatoxoba.pdf
    • https://ludbaegitim.com/calisma2/files/uploads/61545235254.pdf
    • http://chocoenglish.com/_UploadFile/Images/file/20238572972.pdf
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/7e70fa3797468e8e20b1b4f9b4b7d348/sekibukov.pdf
    • http://mdbim.pl/ubezpiecz/obrazy/file/15744137711.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075b78e59168---61493370859.pdf
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b6312d2c6f5---posovof.pdf
    • http://busankid.com/webfiles/board/file///74909803897.pdf
    • https://ceccarbotosani.ro/userfiles/file/kulutezuxagukedone.pdf
    • https://kantankacreative.com/wp-content/plugins/super-forms/uploads/php/files/e786d9b697da93d004b210200e7ea4ad/8302134371.pdf
    • https://webfox.net.au/wp-content/plugins/super-forms/uploads/php/files/44a9a4f9d2e75e1c644dbd5000fb63a3/93188095216.pdf
    • https://puppometalli.eu/file/57921215185.pdf
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607e0e86ca720---98910409022.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607895845d503---zonulunofusamab.pdf
    • http://adance0112.com/upfile/editor/file/xogov.pdf
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ada7844b1a9---32293317543.pdf
    • http://www.lauricedale.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608cbb24badf6---43094568213.pdf
    • https://bem-sa.com/img/file/99787232664.pdf
    • http://shtaket46.ru/page_edit/_samples/userfiles/files/51791142155.pdf
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080db8f7260a---lilepasiso.pdf
    • https://migger.dk/userimages/file/zurexazaduwedigesosimo.pdf
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609ae820d8b0b---zepakupajoromuwamuluv.pdf
    • http://aircond.md/upload_fck/file/64305349039.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_off0000ed33.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xED33 16792 bytes
font_01_sfnt_off00010545.bin
37ce01a8a47408fcd0ae7939507eafd4d4af28547a275b85160bfa342fa72a9e
pdf-font-stream PDF embedded font (sfnt) at offset 0x10545 17096 bytes
font_02_sfnt_off000131e7.bin
82a47e446dce23c48f3dd094946213fd91b5fbb0117bad2dc941b6bc07007cc7
pdf-font-stream PDF embedded font (sfnt) at offset 0x131E7 10592 bytes