Malicious PDF — malware analysis report

Static analysis result for SHA-256 a25cffc30cd2f23b…

MALICIOUS

PDF

82.3 KB Created: 2021-10-14 19:56:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 7aa881449d5d3e17b6f22dfa170d53be SHA-1: 026e3d5c5327aacc3dbd249c02e3fa3bb4920206 SHA-256: a25cffc30cd2f23b4ebaa87ac69b77289c2021bf28778c9ee9ab118baf21f719
134 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded links to external PDF files, many hosted on suspicious domains, suggesting a link farm or phishing lure. The presence of a 'download button' heuristic further supports a social engineering attack pattern aimed at tricking users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://xn--c1adbeke4asdefy.xn--p1ai/ckfinder/userfiles/files/fupowatuxawefamorijisol.pdf In PDF document text
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/resovudexigoresulipuf.pdfIn PDF document text
    • http://arcos-eff.it/userfiles/files/weratud.pdfIn PDF document text
    • http://babijie.com/upload_fck/file/2021-9-13/20210913223846542841.pdfIn PDF document text
    • http://drukarnia-skawina.pl/app/webroot/media/files/89280641343.pdfIn PDF document text
    • https://deltaguvenlik.net/userfiles/file/28806951348.pdfIn PDF document text
    • https://szallas-karpatalja.com/upload/mobunamosesini.pdfIn PDF document text
    • http://klusjesindex.nl/images/uploads/44200632148.pdfIn PDF document text
    • http://greensquares.in/userfiles/file///48544069257.pdfIn PDF document text
    • https://zzhqhi.com/d/files/98565134913.pdfIn PDF document text
    • http://archiw.gbpopatowiec.pl/img/upload/files/91108115780.pdfIn PDF document text
    • http://everestlodgelukla.com/userfiles/file/rupagedebaj.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614f7cf28cab4---gebafipuzowijuxi.pdfIn PDF document text
    • https://mobspace.xyz/web/img/podborky/files/98645750808.pdfIn PDF document text
    • http://studiotrusso.it/userfiles/files/zenorojajeraxodasafopuk.pdfIn PDF document text
    • http://maremania.net/img_pagine/file/16092162642.pdfIn PDF document text
    • https://aviatroglo.fr/IMG/file/26137144565.pdfIn PDF document text
    • http://master-sign.ru/ckfinder/userfiles/files/muxefafa.pdfIn PDF document text
    • http://yuemeism.com/uploadfiles/files/47712491000.pdfIn PDF document text
    • http://gr-chem.com/upload/files/xukikagitojabiguvaxadakal.pdfIn PDF document text
    • http://ambvetsanprospero.eu/userfiles/files/90430302531.pdfIn PDF document text
    • http://artc-polymers.com/upload/images/files/bezadaneg.pdfIn PDF document text
    • http://matchonusa.com/uploads/files/55148087695.pdfIn PDF document text
    • http://cpgny.com/userfiles/files/6282651386.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/TxADE9PCSUw/uplcv?utm_term=6th+science+guide+downloadPDF 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_off0000d2eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2EB 10804 bytes
SHA-256: eee3109a7cd59e165dbc603c6c31da003d5215e99f6fefe37773d26cd5dde2f4
font_01_sfnt_off0000ebaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBAA 21932 bytes
SHA-256: 1492f488e1380078f3957abdfa89a054148cd7a8cff1ed0ed76b0d525bbe22e6
font_02_sfnt_off0001235d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1235D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1