Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac82ce18d5d043df…

MALICIOUS

PDF

87.5 KB Created: 2021-06-28 01:09:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 43b7d549c602409433be166ea49a5407 SHA-1: 3c4cf8434e02e720ff9f5cd4c408666d740a113e SHA-256: ac82ce18d5d043df7e785f3196514d5048944476647a22a27482af2d3b04c917
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code or redirecting users. Heuristics indicate the PDF acts as a link farm, pointing to multiple compromised or disposable hosting sites, likely to obscure the final malicious destination. The ClamAV detection and ML classifier strongly suggest malicious intent, consistent with phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/50c9c74602a27f0eeec2291adccd8ef9/sakudot.pdf
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16093808390e8d---maridazigotewararox.pdf
    • http://coffee33.ru/archive/file/47703843519.pdf
    • http://euro520.net/userfiles/file/1621351784313978504.pdf
    • http://daieimotors.com/js/upload/files/pefamajed.pdf
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/6313e4a48e5f63e481e0dc4923d4d4b6/31059971828.pdf
    • http://www.annaleehuber.com/content_files/file/4385611403.pdf
    • https://twr1115.net/files/fckeditor/file/69106306085.pdf
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/43731edd1303bff4156704ea5f6296db/veraje.pdf
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/2jtg5vl18j59mdb7h8staq9s50/15061415228.pdf
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160838b60cc2fe---fazenote.pdf
    • http://benthanhsgfarm.com/images/uploads/files/66080898446.pdf
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084b538e3578---92597997232.pdf
    • https://banghenails.com/upload/file/sizugonovewudaxave.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/u93vlttv73hriha9g29bvk3612/62909163610.pdf
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/0f080e689adbd8b4e02a2d0db5609061/dafoza.pdf
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608790895b594---90587192183.pdf
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f214726c10---30939306087.pdf
    • http://beijingxinzhi.com/userfiles/file/20210507095517_1230243740.pdf
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/ddc7dcda4d5849f4f7f495b3ca1aae87/35754322292.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160cb0454ad850---farojerupimulisivu.pdf
    • https://itchanoi.vn/uploads/news_file/94518612780.pdf
    • https://shidoremicrosys.com/media/tezenif.pdf
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a58e36e302---vafezixugalupepij.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=optional+questions+and+answers
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f18f.bin
e43a214f2fa8d1e1034055700a376d2e60f0bd36764ec3af9cb7556f6a45ac83
pdf-font-stream PDF embedded font (sfnt) at offset 0xF18F 17692 bytes
font_01_sfnt_off00012018.bin
aceb364df3bc9c2118c893af2a215be0630f3369297bc1c6c2bb864166592dba
pdf-font-stream PDF embedded font (sfnt) at offset 0x12018 10740 bytes
font_02_sfnt_off000138cd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x138CD 16792 bytes