Malicious PDF — malware analysis report

Static analysis result for SHA-256 becae3360696ab5a…

MALICIOUS

PDF

75.7 KB Created: 2021-09-17 11:46:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f7103074777d4b223ff9ed4f2d4e3fcf SHA-1: d20398dbca1fe467d6cbf302cc4baa1d024d94fc SHA-256: becae3360696ab5a7f088e63b881c6a03917308246c14e06b7a93aa908ff80be
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ML classifiers and ClamAV, specifically flagged as Pdf.Phishing.Trojan. Heuristic analysis indicates it functions as a link farm, directing users to compromised WordPress upload storage and other disposable hosting sites. The embedded URLs, while some are marked benign, are part of a broader pattern of redirecting users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://vinasimex.com/uploads/file/97515991062.pdf In PDF document text
    • https://rt-totaalafbouw.nl/userfiles/file/99682516186.pdfIn PDF document text
    • https://kp-bs.ru/upload/files/80125921206.pdfIn PDF document text
    • http://kiuanai.com/userfiles/file/53981114109.pdfIn PDF document text
    • https://mccartha-cobb.com/userfiles/files/29123501141.pdfIn PDF document text
    • https://www.wemservice.com/ckfinder/userfiles/files/kutut.pdfIn PDF document text
    • https://textosl.com/upload/editor/file/48262510516.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a86fa168b1---10304241.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/16135d763a7206---fewaperawowinajan.pdfIn PDF document text
    • http://otestmanager.org/club/data/userfiles/file/20210904142103.pdfIn PDF document text
    • http://oprandi.it/userfiles/files/kuxemefapawokirinezux.pdfIn PDF document text
    • http://ngor2-3.com/file_media/file_image/file/rumezoneferomaseb.pdfIn PDF document text
    • http://halaljones.com/uploads/files/tajugipudo.pdfIn PDF document text
    • http://wsp.pl/userfiles/file/jetugo.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/2fb7ec86d97fedce1f68faec8c89b97f/68104271676.pdfIn PDF document text
    • http://xn--4k0b43gkwo4gn.com/upload/editor/file/33634938568.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d8f470dc38---34823410922.pdfIn PDF document text
    • http://fzsvybbs.at/userfiles/file/soporedesoganovumizij.pdfIn PDF document text
    • https://mmagame.com/userfiles/file/14365999447.pdfIn PDF document text
    • http://kor-ra.ru/UserFiles/file/jumav.pdfIn PDF document text
    • https://porfic.com/fotos/file/12285441940.pdfIn PDF document text
    • https://posaonakosovu.com/ckfinder/userfiles/files/woxuzi.pdfIn PDF document text
    • http://chetaomaynganhnhua.com/uploads/files/28836702495.pdfIn PDF document text
    • http://iphonedown.com/ckfinder/userfiles/files/42675224812.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=kompozer+download+for+androidPDF 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_off0000c528.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC528 10532 bytes
SHA-256: 660d713ffeeff4ea0921bf95a97ba2eaf887664db96d7ae8c2f8a23136c603f8
font_01_sfnt_off0000dd18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD18 16968 bytes
SHA-256: a49e80b89f6f04267ecbd69d6204554e7b83ea170bbaa40bdd63642804ccfa14
font_02_sfnt_off000108fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108FE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1