Malicious PDF — malware analysis report

Static analysis result for SHA-256 87163d708dd41560…

MALICIOUS

PDF

86.5 KB Created: 2021-09-08 15:21:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9e8685c460aae598c80191bc7912b63c SHA-1: 1bca45f34b014a1475fa2ae72afb366ad1ab0d81 SHA-256: 87163d708dd41560ee228641bca7cbe68b34df754b3a0dee75b2ddd6d6796ab1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is often used to redirect users to malicious websites or download further payloads. Several heuristics indicate the presence of link farms and compromised CMS uploads, suggesting an attempt to host malicious content. The ClamAV detection as 'Pdf.Phishing.Trojan' further supports a malicious intent, likely involving phishing or trojan distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/7877a9e6113aaf48108e9d2b1ea88aa7/15704494051.pdf In PDF document text
    • http://splogservice.ru/content/file/69424132899.pdfIn PDF document text
    • http://old.arcnet.org.tw/ckfinder/userfiles/files/36559878776.pdfIn PDF document text
    • https://aitalk.vn/upload/files/91158828926.pdfIn PDF document text
    • http://nissanotogovap.vn/uploads/images/files/86207558883.pdfIn PDF document text
    • https://mmagame.com/userfiles/file/kosawatarunavivi.pdfIn PDF document text
    • http://knipia.com/userfiles/file/sovidikugomedud.pdfIn PDF document text
    • http://physio-praxismitte.de/userfiles/97228843002.pdfIn PDF document text
    • http://hodinovysoused.cz/upload/file/47576823354.pdfIn PDF document text
    • https://www.sophrologue-nimes.fr/upload/news/files/mifemo.pdfIn PDF document text
    • https://graphicart.ro/fckfiles/file/diridanadedulimoxitoxi.pdfIn PDF document text
    • http://greenvisioninternational.gm/userfiles/file/xolivusupukedegigabura.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/161361b9f1931a---zosupilarifobekezen.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/c74f306b938606db0dd4e02775c49cc1/42223681549.pdfIn PDF document text
    • https://aquaprosmart.com/userfiles/files/vadefofufo.pdfIn PDF document text
    • http://alimentosldm.com/userfiles/file/zexemenugitiwavitubibuvum.pdfIn PDF document text
    • https://blugarden.eu/file/26648924556.pdfIn PDF document text
    • http://superbarter.sk/media/file/fisitasixakefutikow.pdfIn PDF document text
    • http://vako.vn/app/webroot/uploads/files/13321393552.pdfIn PDF document text
    • http://premiumcsp.com/uploads/files/35389695219.pdfIn PDF document text
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/7cde8aa1e9de2108c1f755afe2b13e46/50037937431.pdfIn PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130372268ece---kubupup.pdfIn PDF document text
    • https://bookmyexcellence.com/bookmyexcellence/js/ckfinder/userfiles/files/mizalu.pdfIn PDF document text
    • https://autoradiator.mn/uploads/ckfinder/files/13628005098.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=federalist+no+10+pdfPDF 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_off0000f189.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF189 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001099b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1099B 16788 bytes
SHA-256: 7f7fd7f57cc663246875cdb97ea22be71e396abce93badb29f16aa4e8cbf41b4
font_02_sfnt_off00013405.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13405 10640 bytes
SHA-256: b5b38f779fe7dfe31378fa697280d28688882b4986673017afb8239edafdd4ce