Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff5590a05931242b…

MALICIOUS

PDF

75.8 KB Created: 2021-09-18 07:57:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f7fb5a4ac4b8f43926373199e5de7101 SHA-1: 02bb11c3dcffbb30d64b0caf0fd7f7cde1ab79fe SHA-256: ff5590a05931242b3212ab63e4916f123c63110bd317a66ea7f54c2396e5ef3c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs, many pointing to disposable domains and configured as a link farm, suggests a phishing or malware distribution campaign. Although no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://kunjipsc.com/uploads/files/dajunobavus.pdf In PDF document text
    • https://kenhquangcao.vn/uploads/files/44547913324.pdfIn PDF document text
    • http://pierrevillers.fr/mairie_files/file/55616511684.pdfIn PDF document text
    • http://musicfriend.vn/public/default/ckeditor/files/23846464253.pdfIn PDF document text
    • http://aeon-dev.com/uploads/files/202109040406134957.pdfIn PDF document text
    • http://maternites-catholiques.org/ressource/site-image/files/molasonibukinikekaluxo.pdfIn PDF document text
    • http://erpsamik.com/ckfinder/userfiles/files/8490468077.pdfIn PDF document text
    • https://happycolaborativo.com/uploads/files/41061928863.pdfIn PDF document text
    • http://gibisch.org/files/files/62432114347.pdfIn PDF document text
    • https://o-dance.com/upload/files/tawipetipeniritegelajaw.pdfIn PDF document text
    • http://www.integra-cr.cz/administrace/ckfinder/userfiles/files/61468594219.pdfIn PDF document text
    • http://bouwbedrijfansing.nl/userfiles/file/85008452138.pdfIn PDF document text
    • https://vishalahospitality.com/ckfinder/userfiles/files/nakotegevisusixu.pdfIn PDF document text
    • https://westhygiene.hu/editor_up/46888073656.pdfIn PDF document text
    • http://alexdisinfestazioni.com/userfiles/files/lomagonenogifes.pdfIn PDF document text
    • http://ohmamakitchen.com/uploads/files/18316178352.pdfIn PDF document text
    • https://fsreloading.com/userfiles/files/84174543953.pdfIn PDF document text
    • http://www.sctiec.com/up_files/FCK/file/nuvibigagefewu.pdfIn PDF document text
    • http://citranco.com/users/files/tugiriteba.pdfIn PDF document text
    • http://old.bgk-meshkova.com/ckeditor/ckfinder/userfiles/files/godoviwogememewonidoduro.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/l7cg9m0nvcb8uo0t4ff8snpqik/27107459766.pdfIn PDF document text
    • https://tkquiz.com/userfiles/file/wuzeke.pdfIn PDF document text
    • http://sanalights.com/admin/admin/uploadfiles/file/29207158720.pdfIn PDF document text
    • http://victoryelectricalsupply.com/ckfinder/userfiles/files/kajigo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=vidmate+full+hd+meinPDF link annotation
    • 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_off0000c4f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dd09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD09 17572 bytes
SHA-256: bfbf22bf03da420eb110a397dec6cddd18e42d5a7be036d9af6905321b24ec39
font_02_sfnt_off00010a6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A6C 10300 bytes
SHA-256: b10f465c364b202c8b6b10c05d36d41d9e63f2f3f4ffa1c1161ee1f83a9621c3