Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5eb3d4834ac7531…

MALICIOUS

PDF

86.1 KB Created: 2021-09-18 16:21:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 034c98c0f5d0a902a54261b184935387 SHA-1: 4db58b03652925a266ecf489cd43a131320e159b SHA-256: c5eb3d4834ac75311312b67bc6098f6678bc1d95529f7321504fdf950e3221e6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple distinct hosts, some of which are compromised CMS uploads or disposable hosting. While no scripts were extracted, the presence of numerous URLs suggests an attempt to lure users to external sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://hyosungulf.com/uploads/file/79821498063.pdf In PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161336eff2e583---20353964603.pdfIn PDF document text
    • http://xn--42-6kcdlkbomh7beggito5p.xn--p1ai/userfiles/file/94238769887.pdfIn PDF document text
    • http://cambresisemploi.fr/ckfinder/userfiles/files/zoketipulejagujexo.pdfIn PDF document text
    • http://haiannweb.com/uploads/files/vulomexizefodopagaraj.pdfIn PDF document text
    • http://mudrkanuch.sk/editor_uploads/system/files/vopatovole.pdfIn PDF document text
    • https://cottonweb.net/userfiles/file/sekuz.pdfIn PDF document text
    • https://likeevent.it/writable/public/userfiles/file/fosozuwefovegif.pdfIn PDF document text
    • https://bosingels.nl/ckfinder/userfiles/files/ludux.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/m6okf488vaqja9l37iardgnp96/titegipugikupofaniviti.pdfIn PDF document text
    • http://yakutiaprime.ru/SITE/files/editor/file/xetilimexukinujifulibew.pdfIn PDF document text
    • http://zeminyerkaplama.com/upload/ckfinder/files/betavapagiriwalifemod.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/d97250736bc8a1562d36cb3cefab7b12/bawivodonijowik.pdfIn PDF document text
    • http://megamento.com/_UploadFile/Images/file/pamojo.pdfIn PDF document text
    • http://igigeothermal.jp/userfiles/file/13276203414.pdfIn PDF document text
    • http://ace-pharm.com/upload/files/17912415227.pdfIn PDF document text
    • http://savalis.ru/userfiles/file/ririgofetigupexerod.pdfIn PDF document text
    • http://sandsflooring.co.uk/ckfinder/userfiles/files/delososanerizizedag.pdfIn PDF document text
    • https://tiemhoamo.tiemhoahaibara.com/data/dulieu/files/20047557371.pdfIn PDF document text
    • http://studiosantomauro.it/userfiles/files/zenokidofakalekakuturiz.pdfIn PDF document text
    • http://bagliodeimille.it/userfiles/files/34091242664.pdfIn PDF document text
    • http://www.ruben.pl/ckfinder/userfiles/files/77258920812.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=race+2+full+moviePDF 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_off0000ea60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA60 18924 bytes
SHA-256: 0f3f1fda86d50fcbfdc43fce7fd2815b84402f42d209a8a3838e19f4a81db2a1
font_01_sfnt_off00011b91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B91 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000133a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133A8 10360 bytes
SHA-256: 6ea1bacfd36caa82dfa9248dfacd023d664190349db12fcaf13caab2ec0f941a