Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9f15af95a1ebe45…

MALICIOUS

PDF

83.9 KB Created: 2021-09-21 12:11:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 05a7b6a43c1d73fc085eee4981b34a1c SHA-1: db1113a7aba292489a0e42f2e1fcf254af2d9f18 SHA-256: d9f15af95a1ebe45cb91d29476357095c7a931778511fc31cac3b1a881b608bb
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm with numerous external URIs pointing to disposable hosting, designed to redirect users. The document body is heavily obfuscated and unreadable, suggesting it's not intended for user interaction but rather to host malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://catamma.ru/uplcv?utm_term=things+starting+with+e PDF link annotation
    • https://worldcastlive.com/userfiles/file/16282245841.pdfIn PDF document text
    • https://drrajanmahtani.com/userfiles/files/vizaxe.pdfIn PDF document text
    • http://fotostudiovaccari.it/userfiles/files/ruxumumesupafosovirumalib.pdfIn PDF document text
    • http://salman-group.com/userfiles/file/51340649275.pdfIn PDF document text
    • http://menifee.hanasushichoice.com/uploads/files/levuzakenilelawasamutiwo.pdfIn PDF document text
    • http://tranindo.com/Uploads/userfiles/files/36540102048.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/jadoxetusavisufamop.pdfIn PDF document text
    • http://dieta-plus.pl/userfiles/file/nodomubufamewaramimimo.pdfIn PDF document text
    • http://alfavit.tv/userfiles/file/nizapokujoleguwok.pdfIn PDF document text
    • http://northmarking.com/userfiles/files/74810431530.pdfIn PDF document text
    • https://hfbee.tw/upload/ckfinder_temp/files/20210921102718.pdfIn PDF document text
    • http://cathugo.de/res/wysiwyg/file/mamalixofe.pdfIn PDF document text
    • http://mprime.net/ckfinder/userfiles/files/38224918092.pdfIn PDF document text
    • https://deepex.hu/hirek/files/4391155599.pdfIn PDF document text
    • http://mamaskitchenorder.com/uploads/files/xigutemusemugujirumep.pdfIn PDF document text
    • http://ultraljud.nu/bild/files/gulaganog.pdfIn PDF document text
    • https://duongthuy.net/userfiles/file/71149280289.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/161466cae2c934---delitagotevisedudojose.pdfIn PDF document text
    • https://jin-hung.com/userfiles/file/dosonu.pdfIn PDF document text
    • https://mimpisiluman.com/contents/files/sekopomo.pdfIn PDF document text
    • http://srcchaika.ru/files/uploads/files/49850417788.pdfIn PDF document text
    • http://xn--80aikni6a0b.xn--p1ai/images/file/37246574987.pdfIn PDF document text
    • https://bio-obst-und-gemuese.de/userfiles/file/fowesizejaj.pdfIn PDF document text
    • https://gizaviation.com/uploads/files/japobaxaj.pdfIn PDF document text
    • https://tranthachcaodanang.com/uploads/image/files/70016218595.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_off0000e2a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2A0 18456 bytes
SHA-256: 4b133300cc56532dc0eb005380740f05495ea1b59153a004bc1c0c8a259c774e
font_01_sfnt_off0001130b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1130B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012b22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B22 10268 bytes
SHA-256: 6cee807944a5c5f8ea308ad1041f8c02f64150580d49c172fcadd50a03699463