Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1b7bad346910714…

MALICIOUS

PDF

71.5 KB Created: 2021-09-26 02:05:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e45539a219b1e6fe1af8ae43c93f3fd1 SHA-1: cfaa73d004abdadc669509c0ce0bb37b751c6e78 SHA-256: f1b7bad346910714106a239ccd5df5c111ad79da5086d4a86b44404e520ea4c7
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Heuristics indicate it functions as a link farm on disposable hosting, with numerous embedded URLs pointing to PDF files. The 'SE_CALLBACK_LURE' heuristic suggests a phishing or tech-support scam pretext, aiming to trick users into visiting these links.

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
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://infrive.ru/uplcv?utm_term=best+drawing+app+android+2020 PDF link annotation
    • http://prosquash.by/data/lozixumegesiruxusim.pdfIn PDF document text
    • http://xn--o39a91gvwm83kbsn.com/FileData/ckfinder/files/20210908_6541E2A4D1C54F4D.pdfIn PDF document text
    • http://abwcrainhwy.com/uploads/files/17411224271.pdfIn PDF document text
    • http://occahomesearch.com/userfiles/files/13319242795.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/5f163356b41c851da3434520f18fe579/5464945813.pdfIn PDF document text
    • http://phatnang.com/media/ftp/file/32078238262.pdfIn PDF document text
    • http://kunjipsc.com/uploads/files/visisiriri.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/50945241198.pdfIn PDF document text
    • https://majubesar.com/contents/files/29485655571.pdfIn PDF document text
    • https://j26clean.com/upload/files/bunex.pdfIn PDF document text
    • https://atlanticcompact.org/userfiles/files/65619207571.pdfIn PDF document text
    • https://cincia.ro/ckfinder/userfiles/files/6358027714.pdfIn PDF document text
    • https://alpinashop.rudy-ra.com/files/76505803747.pdfIn PDF document text
    • http://www.stadion-zarya.ru/ckfinder/userfiles/files/48257415188.pdfIn PDF document text
    • http://moto-bike.pl/userfiles/file/14354151067.pdfIn PDF document text
    • http://studiodispirito.it/userfiles/file/lanemab.pdfIn PDF document text
    • http://exmar.it/foto_fck/file/dodamugikexiwakitisumab.pdfIn PDF document text
    • https://fertilizerproductionprocess.com/d/files/pawuboburimolasubewana.pdfIn PDF document text
    • http://www.majbrno.cz/uploads/files/gelojolilanek.pdfIn PDF document text
    • http://eis-pieschel.de/UserFiles/File/39862045829.pdfIn PDF document text
    • https://micro-logic.ro/images/uploaded/file/xikonitetewiroroboboza.pdfIn PDF document text
    • https://ctapigroup3.com/contents/files/kaxabaloxulur.pdfIn PDF document text
    • http://tfe-design.dk/userfiles/file/42381626766.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/de1621bb7fd95366287b057305f21a98/56801760314.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_off0000b108.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB108 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c91a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC91A 17864 bytes
SHA-256: 510a3a6fd2920a696a461c7887de9ea8fe68a3905d4dff4c97cebde660ef8f8a
font_02_sfnt_off0000f759.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF759 10900 bytes
SHA-256: 2b49539ca03b5623d4250935cfd1d64ba79c3e7b656b521ba6b5757456a52129