Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f8f046a55560615…

MALICIOUS

PDF

69.3 KB Created: 2021-09-26 16:07:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: c3e890c1da34f824459c84d29602bbd4 SHA-1: 0b486fe74dfe3bc55719fb56e4a3dbd166fe326c SHA-256: 4f8f046a5556061528469b80d90c3f42c41b8dd19605c953a853417616501f98
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ML classifiers and ClamAV. It contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution attempt, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

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://crysiq.ru/uplcv?utm_term=fundamentals+of+nursing+final+exam+questions+pdf PDF link annotation
    • https://forssah.co/userfiles/file/gikobujakufaguvosogi.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/161414e6f20cbc---liwozabigewes.pdfIn PDF document text
    • http://saraya-shop.ru/upload/files/dalulezisawuloboxi.pdfIn PDF document text
    • https://suny.cz/files/file/63397964785.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/3b1c5c4253f8b0343644d55847a253c6/kububozavegewe.pdfIn PDF document text
    • https://valeaflorilor.ro/img/uploads/file/868471855.pdfIn PDF document text
    • http://s2ipower.com/survey/userfiles/files/4052821085.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/161403c29bf7e0---vefomip.pdfIn PDF document text
    • https://groupekheidri.com/ckfinder/userfiles/files/sulosatajidoluzowutisut.pdfIn PDF document text
    • http://saltokisport.com/uploads/files/telofijeturelisosigoxuroj.pdfIn PDF document text
    • http://e-sheremet.com/img/zujigidisakatipikuxi.pdfIn PDF document text
    • https://un7un9b3rl1pa7-99.com/contents/files/tuwiwex.pdfIn PDF document text
    • https://saatyapi.com/upload/ckfinder/files/zenob.pdfIn PDF document text
    • http://rainhouse.kr/data/editor/file/209469348613e3adc68108.pdfIn PDF document text
    • http://pm-ural.com/uploads/files/gitumobijekaronanifagad.pdfIn PDF document text
    • http://biomehl.com/images/content/files/makix.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142f12bd6a8c---dunamigupovevalojazosisi.pdfIn PDF document text
    • http://mygiftltd.com/userfiles/file/lunefuxifofipenejozisit.pdfIn PDF document text
    • http://streetnn.ru/data/upload/ck/files/53526700115.pdfIn PDF document text
    • https://wickedcheesy.com/images/file/76697403574.pdfIn PDF document text
    • http://getvisa.ru/images/File/66474285045.pdfIn PDF document text
    • http://nagymester.com/userfiles/file/wonep.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/1614294a627e14---sojajudiwo.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/2107ca9effb1d3bb757d9fbacf2ebd86/xaxowifapevomaforen.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://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_off0000b366.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB366 11168 bytes
SHA-256: ed472fdae3a53af51cc3e8f2a3038dae350d4915e9b0e51e0a0e85489ee4172f
font_01_sfnt_off0000ccf1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCF1 15440 bytes
SHA-256: bae892fbb947aa12b4257abea9bfc5f817ce4e5952910d683af6446f5f5c0ed4
font_02_sfnt_off0000f3da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1