Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b378cc4b04b8c86…

MALICIOUS

PDF

87.6 KB Created: 2021-07-08 12:18:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: dcb36ca2411a785dc58bfa5d5c23754b SHA-1: da34998a62e23e490951c36a96d859a4764154cd SHA-256: 5b378cc4b04b8c8682f535e32ac2077357689b8380fa3c250e649a661ac6147a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to compromised WordPress upload directories and other disposable hosting, indicating a link farm designed to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's part of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/721389eea48c325bd01833663db17c9b/lepovekobuzajolitekawu.pdf In PDF document text
    • https://pichsas.com/file/5628195833.pdfIn PDF document text
    • https://virtualpulse.eu/UserFiles/file/37845323242.pdfIn PDF document text
    • http://ronaldtan.nl/images/photo/ledobirixesobunozov.pdfIn PDF document text
    • http://topoint.cc/userfiles/fckFile/20210623114353.pdfIn PDF document text
    • http://www.cddfct.com/up_files/file/23517577425.pdfIn PDF document text
    • http://verynailscm.com/user_img/file/41528236694.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/7466526023.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a1967f89d23---33601843639.pdfIn PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/001ms7397puv683lhnu1ad5ff0/lirivigagofitobe.pdfIn PDF document text
    • http://akinmedical.com/uploads/file/damawevuwux.pdfIn PDF document text
    • http://nkcophs50threunion.com/clients/0/01/014062e559e26c1cf0711bcec4e573ae/File/60520327298.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6e035a7f2a---51426835059.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/0376e0d892674a94f9289a8f9bfe26cc/mitezuzoxivekowa.pdfIn PDF document text
    • http://fqcycpa.com/jingkelun/userfiles/files/20210617130713.pdfIn PDF document text
    • http://animationcoach.com/userfiles/file/61331275956.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/hg9cpci84b2snb4rkc5sialqhd/sowenafuj.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/ree9gvv9v5jojdkjn1ga6gq09h/zozenemewaxukamanokut.pdfIn PDF document text
    • http://roxburyhs1987.com/clients/63080/File/zatifipesikakaputefewew.pdfIn PDF document text
    • http://franklinbristerharveyfamily.com/clients/a/a8/a8910385c57dfddac3c6311e2bd1422e/File/zikatupij.pdfIn PDF document text
    • http://aklond.com/UploadFilesfile///2021042910532858.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/160872a77510bd---ponudov.pdfIn PDF document text
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/5b0eec1b9e2d0ebd68a497c3394b1641/7680459230.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/236f0e23c8c39aa00d0f94d269dc5015/92654458848.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/pb8459f3ckahq9cme9cm61g6pn/48027435351.pdfIn PDF document text
    • https://bestcoloringpages.com/userfiles/file/52884907681.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=theme+of+the+lesson+by+toni+cade+bambaraPDF 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_off0000f382.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF382 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010b94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B94 16900 bytes
SHA-256: ee5bdf8f5baf334abef5fc28e418ee86bc062cd5871e6a489d7d8a0a3bb89235
font_02_sfnt_off0001375f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1375F 10956 bytes
SHA-256: 75357b9cae253fea28272cb3f4b037c1e8020d275606d7f40be6fe1a4b0439b3