Malicious PDF — malware analysis report

Static analysis result for SHA-256 c685c43933aaf4a1…

MALICIOUS

PDF

92.4 KB Created: 2021-07-08 08:21:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: a76da1f0340e6d59d9bbc220d3d4a9bf SHA-1: 0155e625af8c20eef8101a0d390afaa60bda4a1e SHA-256: c685c43933aaf4a196edd33b936591ad643f4dc2a4a21ec08c50750ed16f73d4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan threat. It contains a link farm pointing to various compromised CMS upload locations and disposable hosting, suggesting an attempt to distribute malicious content or phish users. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document designed to lure victims into downloading further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://brtim.com/uploads/wysiwyg/files/71830814412.pdf In PDF document text
    • http://banglatalkies.com/dynamic-images/cms/file/58456478233.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a99f43734f2---nirifebosoxizufuwimumukel.pdfIn PDF document text
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/708a483de751978903f6d8daca8f0b2f/99773672348.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160a15a65913ac---fowewa.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/160bdbb2d8260c---52960689412.pdfIn PDF document text
    • http://kondicionery-vidnoe.ru/upload_picture/file/7049451163.pdfIn PDF document text
    • http://divorce-difficile.fr/userfiles/file/kijugawa.pdfIn PDF document text
    • https://vannordenvastgoed.nl/userfiles/file/gigaduxojemabokuxateror.pdfIn PDF document text
    • http://ever-pioneer.com/upload/files/tipasawu.pdfIn PDF document text
    • http://www.lnk-creation.fr/upload/file/31941116818.pdfIn PDF document text
    • http://accronline.com/userfiles/file/53939391502.pdfIn PDF document text
    • http://lowry-averyreunion.com/clients/c/c0/c0e4e7922159a76f956c19110b7bfeb7/File/25398347389.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210630025744403641337.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160749e8950aa3---62815959913.pdfIn PDF document text
    • https://by-express.com/upfiles/editor/files/rilosupotemuru.pdfIn PDF document text
    • http://www.evisiontiendaonline.com/ckfinder/userfiles/files/roxogovituvigoladoxofeg.pdfIn PDF document text
    • http://middlegeorgiacoinclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b2165549cc---14009888165.pdfIn PDF document text
    • https://gachbinhduong.com/upload/file/sujegupogusam.pdfIn PDF document text
    • https://condominiovillage.com/userfiles/file/55521763669.pdfIn PDF document text
    • http://skncn.com/u/files/daxanasijatotodojuv.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/4fgkinepqhin2jrddm2quh1d70/66438046409.pdfIn PDF document text
    • https://sheenabusesandcoaches.com/userfiles/file/vizananojezimekinegudifu.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160ade1780548a---79969277167.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=wife+good+morning+imagesPDF 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_off0001089a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1089A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000120ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120AC 16604 bytes
SHA-256: 93b098069981d4146cc94e676a585f5695724a8f924918681042d19e4b9d9be6
font_02_sfnt_off00014b4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14B4F 10548 bytes
SHA-256: 1c8887ed632900aa6de6b4eb615bfc24221f662be6e29bb288cde5deaed0d10a