Malicious PDF — malware analysis report

Static analysis result for SHA-256 b28d3bcb0cb0c555…

MALICIOUS

PDF

87.8 KB Created: 2021-07-01 15:50:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1e44ce1299bd77f725f4e099d698cb0a SHA-1: 96cf565c54507217d9e7d20d1735b1fbf10d7322 SHA-256: b28d3bcb0cb0c55536d3c6cfeeaaa3205ec1addb1a825231efe0f79e59de2d39
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics suggest it functions as a link farm, directing users to multiple external URLs hosted on potentially compromised or disposable domains. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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 https://archism.ru/uplcv?utm_term=greek+letters+to+numbers
    • https://digbijoynath.in/iisc/ckfinder/uploads/userfiles/files/89880612487.pdf
    • https://getadoc.in/ckfinder/userfiles/files/8818175119.pdf
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/c3820611de72913336df67fc94799177/79078117231.pdf
    • http://tsg-edinstvo.ru/userfiles/file/173510451.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c30a62ca091---16801826117.pdf
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160c3a514e1295---munozovexiwodu.pdf
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092b84d7752e---devetikukoposolot.pdf
    • http://rspon.pl/images/wyswig_images/file/2924131918.pdf
    • http://kondicionery-ivanteevka.ru/upload_picture/file/19363175794.pdf
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/a26p7q6eeuqul1oj75bha0u2m2/mimikinadamovan.pdf
    • http://pokorny-podlahy.cz/UserFiles/File/83908185973.pdf
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160b17e6dd725f---rowesudagexotavetati.pdf
    • https://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/410a5941360d7ca6ec8ff01e3155b01a/dojajawasisikumomimix.pdf
    • http://re-view.online/fckFiles/file/36787583741.pdf
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a89e58595b6---zubuwilexovajez.pdf
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/60c6cdc86269a7da07c2601b92dfbfbc/tefumapeki.pdf
    • http://szpital-sulecin.pl/images/fckfiles/file/jumaxo.pdf
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c628b02f654---fagewaxunejofif.pdf
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160842f33b669b---mexenamolirasim.pdf
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ceda782ac67---8955903476.pdf
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/d9c1325fe7b7a1be031e7dd3f61fd2f7/91937142527.pdf
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16082c38cab3c2---salesuwoditoni.pdf
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/6c9f61026e912f9dadb730e509b0554a/mafuwe.pdf
    • 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_off0000ec7f.bin
d36cf53bc5d139c9a9ff59ccf6f7d9282639820fa2fb0f19a89f9d8c7553a864
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC7F 19924 bytes
font_01_sfnt_off000120d2.bin
f65f9a88f8ce0ba916d90b833b4dd83e3e86642f57e4a72d6be8c59bc249fcd6
pdf-font-stream PDF embedded font (sfnt) at offset 0x120D2 10388 bytes
font_02_sfnt_off00013869.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13869 16792 bytes