Malicious PDF — malware analysis report

Static analysis result for SHA-256 a12575735e97d734…

MALICIOUS

PDF

75.2 KB Created: 2021-07-28 01:25:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: b76f375810306483822538f647d92be8 SHA-1: d5f4dec8530a86863fc9fd9e62ed8df3ae2b6f7b SHA-256: a12575735e97d7349c2c4f9ec50dcc21b6a548ef3708e23c802a8dd3b044c7cc
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm hosted on compromised WordPress sites, with numerous distinct hosts and UTM parameters suggesting SEO manipulation. The embedded URLs likely lead to further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • 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://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/chcnn9fv4huh0dd11v77jvr5c4/zazevozuwazinididoduwaded.pdf In PDF document text
    • http://ctyrkolky-gamax.cz/data/dokumenty/28129304304.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/9f337c2f96523ffb2b2bde58b236dce4/gebigidepagamonulax.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608902743f9cb---jifabirewabodebefoxaf.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160833bc90df88---buwutuzedovisuvu.pdfIn PDF document text
    • http://anm-av.de/uploads/files/wotegovanorejipaludejo.pdfIn PDF document text
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/21a3d98aa60525f95956f1e0c67f978f/2233348543.pdfIn PDF document text
    • https://west-holding.com/userfiles/file/sopenatura.pdfIn PDF document text
    • http://alompar.hu/uploads/content_files/files/71068062631.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/8f4f1fcc048daeca757306c187c215f0/929055483.pdfIn PDF document text
    • http://cestovni-postylka.eu/userfiles/file/6285007074.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1739d957c---48419170575.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/53uuh8nsv0sbi8cs3pdb221gq4/tepolugesafovuwos.pdfIn PDF document text
    • http://www.scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/pozatopubusaseg.pdfIn PDF document text
    • http://asremajazi.com/uploads/files/77571011534.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/16080f22636b4d---jokawu.pdfIn PDF document text
    • http://ecogestval.com/userfiles/file/80922087693.pdfIn PDF document text
    • http://graylegalservices.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nibinigoge.pdfIn PDF document text
    • http://vendsol.com/userfiles/file/8147138021.pdfIn PDF document text
    • http://brookhavenclassof1967.com/clients/0/0c/0ca802fc87877f8c548ddf85495caeb2/File/vonat.pdfIn PDF document text
    • http://veraschwemmle.de/fckdata/file/61615587039.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/eab0e516b329a72973a5cf4183084097/59930668887.pdfIn PDF document text
    • https://investmentskillsgroup.com/images/userfiles/file/27479888909.pdfIn PDF document text
    • https://dascalita.ro/app/webroot/files/userfiles/files/niwarosupub.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=spring+worksheets+for+kindergartenPDF 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_off0000c3b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3B9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dbd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBD0 10984 bytes
SHA-256: 9ca6c3b13d89fddaaa8fc78ce5560875c4c038e251a183a79b88b275cac5ad2a
font_02_sfnt_off0000f518.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF518 15676 bytes
SHA-256: 91e6d08806b33234df68436f17bb48dab6683268afa2704e3bb5b0201c39e5d6