Malicious PDF — malware analysis report

Static analysis result for SHA-256 597eb8c94ae821d8…

MALICIOUS

PDF

77.9 KB Created: 2021-09-12 09:06:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c97173a3150d96020ed673cc54ad45fb SHA-1: a6d9917cb2f6a4206b3b75f7beb9f9f3ced62f4e SHA-256: 597eb8c94ae821d84f319a411c1292994b70faf50d49b46693c5b6cba3a16d6f
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, directing users to compromised websites and disposable hosting. The URLs extracted suggest an attempt to lure users into downloading files, likely malware, under the guise of legitimate software.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://sin-hua.org/userfiles/29241819457.pdf In PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c190ebe5f6---miturilur.pdfIn PDF document text
    • https://indoshaolinkungfusociety.com/ckfinder/userfiles/files/17173938239.pdfIn PDF document text
    • http://urgentcarepb.net/userfiles/file/ratesisura.pdfIn PDF document text
    • http://yildizteknikelektrik.net/resimler/files/57654343665.pdfIn PDF document text
    • https://halead.com/uploadfile/1631414024.pdfIn PDF document text
    • http://catherine-massage.com/ckfinder/userfiles/files/sivexegawajujas.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/bokoligodogil.pdfIn PDF document text
    • http://egyptlance.com/userfiles/file/84870043400.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/uekmehrnpnm01ah954gomahl0r/fatewinidese.pdfIn PDF document text
    • http://chromowane.com/userfiles/file/bupufumatujudabofufilaxa.pdfIn PDF document text
    • http://proleague.dk/userfiles/file/15528697717.pdfIn PDF document text
    • http://runhouchem.com/upload/files/rimuxapegijupujo.pdfIn PDF document text
    • https://www.natursany.com/ckfinder/userfiles/files/larejijut.pdfIn PDF document text
    • http://eptesteplelek.com/uploads/file/rikidafo.pdfIn PDF document text
    • https://brothers-music.com/ckfinder/userfiles/files/86083095953.pdfIn PDF document text
    • http://st-communications.com/ckfinder/userfiles/files/55307846001.pdfIn PDF document text
    • http://intertribo.sk/files/leledete.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/5062aeb89cc0f46a9b6ec9a2fece6141/gawimolejolazosusinadof.pdfIn PDF document text
    • http://3mfa.com/images/editor/files/fugoruzudivepo.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/julofefegejidazodamawojo.pdfIn PDF document text
    • https://zlato-stribro-investice.com/upload/files/97059607625.pdfIn PDF document text
    • http://energo-market.ru/sadm_files/19325162837.pdfIn PDF document text
    • https://tradingcall.in/ckfinder/userfiles/files/ralotumivaxisatimumol.pdfIn PDF document text
    • http://inruho.ru/ckfinder/userfiles/files/xevenawida.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=download+need+for+speed+underground+2+full+version+for+windows+7+freePDF 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_off0000cc25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC25 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e437.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE437 16912 bytes
SHA-256: bbb1bd94bb5f3facef6e20cec0bf47c6fb6d48286c0686d79486c02295709be2
font_02_sfnt_off00010ff8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FF8 11000 bytes
SHA-256: a7687f2678fc2e75359c17b80162080964e7ef0553264590d928c6674914ed75