Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c907ad644a1c781…

MALICIOUS

PDF

83.4 KB Created: 2021-09-18 05:11:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c4f7cb557d5ade11ead635ffa7dd528c SHA-1: 8ea58bb274f371faa9535885a964df465efc6e03 SHA-256: 1c907ad644a1c7817e1150fc6c48355e7f2d57faf5adf483a2d61bbaf5290824
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The PDF contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm, suggesting a phishing or malware distribution campaign. No scripts were extracted, but the presence of many external links indicates an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://medvor.ru/uplcv?utm_term=how+to+enlarge+android+keyboard PDF link annotation
    • http://www.integra-cr.cz/administrace/ckfinder/userfiles/files/juvafivutusuvifin.pdfIn PDF document text
    • https://mytopics.it/uploads/file/bijabusuzegorolud.pdfIn PDF document text
    • http://wpklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pevimifexezoxotekezunobir.pdfIn PDF document text
    • https://mahae.hu/files/files/bajuzubegadutitefewu.pdfIn PDF document text
    • http://hiro-seiko.com/upload/files/90681934472.pdfIn PDF document text
    • https://mtmnetwork.net/uploadEditor/files/kegovelatiworo.pdfIn PDF document text
    • https://iskoruma.com/upload/ckfinder/files/12563309894.pdfIn PDF document text
    • http://superazs.ru/images/news/file/68330192042.pdfIn PDF document text
    • https://glozor.com/userfiles/file/48307064670.pdfIn PDF document text
    • http://verduciautodemolizioni.it/userfiles/file/99031372115.pdfIn PDF document text
    • https://fgcrubochi.com.ng/ckfinder/userfiles/files/miwubegutom.pdfIn PDF document text
    • http://sromedical.com/file_media/file_image/file/34388238341.pdfIn PDF document text
    • https://chennothinterios.com/uploads/file/katusemalafa.pdfIn PDF document text
    • https://willes-gb.com/uploads/files/202109090702422613.pdfIn PDF document text
    • http://alsace.annuaire-regional.com/ckfinder/userfiles/files/83130996837.pdfIn PDF document text
    • http://www.dean-cpa.com/files/adminpic/file/vevuwuxufed.pdfIn PDF document text
    • http://marketingnews.fr/images/file/18314291919.pdfIn PDF document text
    • http://aristosaigonhotel.com/uploads/files/26329434886.pdfIn PDF document text
    • http://rewitex.pl/userfiles/file/pibenov.pdfIn PDF document text
    • http://klubalfa.org/img/userfiles/file/vujuwekoli.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/b8108df4d111bfce41d0277fe0b5eab1/xafukotukitaje.pdfIn PDF document text
    • https://nutricount.cz/UserFiles/File/fuvumokolufuwedufuvalow.pdfIn PDF document text
    • https://globalcircle.club/userfiles/file/44906155196.pdfIn PDF document text
    • https://inprovitcentroamerica.com/ckfinder/userfiles/files/87228047100.pdfIn PDF document text
    • http://xn--80adic7alej3d.xn--p1ai/userfiles/file/90976022577.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_off0000de8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE8B 10676 bytes
SHA-256: 4149964e60899edc44d85aff2048760b790e1331edc8fcc5c8cd5ad39b1cff4b
font_01_sfnt_off0000f6ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010efe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EFE 18752 bytes
SHA-256: f93a8b8cb914ede38f682feea95f9691a172c0a160186f1003203dd12be1a360