Malicious PDF — malware analysis report

Static analysis result for SHA-256 939f5a0c3ba54f74…

MALICIOUS

PDF

82.4 KB Created: 2021-09-14 00:20:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 69246e1c721f5f1ed05b26a3870d96ae SHA-1: afeebfc95a18e824e689fd735d03d74c455b52e8 SHA-256: 939f5a0c3ba54f74885e0b35b7ce8659690f7634b0f3379f401a7a45127f9eaa
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, hosting numerous PDFs on disposable domains, and contains external URIs pointing to potentially malicious content. The document body is heavily obfuscated, preventing analysis of its specific content, but the overall structure and heuristic firings strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://bastola.org/userfiles/file/22927607183.pdf In PDF document text
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fikifusogenozefegakex.pdfIn PDF document text
    • http://knipia.com/userfiles/file/zoreporizusipakeg.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613a9d7c3d2d8---42625090656.pdfIn PDF document text
    • http://studiosaletta.it/userfiles/files/rogofemagipagoraludafamop.pdfIn PDF document text
    • http://peak-experience-europe.com/images/blog/file/53554602184.pdfIn PDF document text
    • http://paroissedementon.fr/upload/files/sogeva.pdfIn PDF document text
    • http://tweddlefoto.com/files_contenidos/upload/files/7279736210.pdfIn PDF document text
    • http://bycongroup.com/UserFiles/file/43955196642.pdfIn PDF document text
    • http://droneducational.com/admin/userfiles/file/nenusij.pdfIn PDF document text
    • https://stoneappeal.in/FCKeditor/file/zojujowunudafijawadukege.pdfIn PDF document text
    • https://dacinsara.ro/fckfiles/file/11854642062.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/161338e9faec00---xidazovazezomitegigumibi.pdfIn PDF document text
    • https://hazeloyun.com/calisma2/files/uploads/sozixulirewepomivemota.pdfIn PDF document text
    • http://anhuizhkj.com/upload_fck/file/2021-9-13/20210913204238682253.pdfIn PDF document text
    • http://facyt.com.ar/ckfinder/userfiles/files/tusumalonoze.pdfIn PDF document text
    • http://rld-carbon.com/file/zobujal.pdfIn PDF document text
    • http://jr-bang.com/uploadfiles/20210913181736.pdfIn PDF document text
    • https://jamurgoreng.net/contents/files/fewudesujasemuvizemoro.pdfIn PDF document text
    • https://parlagame.com/calisma2/files/uploads/lipogifase.pdfIn PDF document text
    • https://digireg.it/upload/67696151995.pdfIn PDF document text
    • http://webinaris.org/ckfinder/userfiles/publics/files/96177280685.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+open+phone+if+you+forgot+patternPDF 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_off0000dc2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC2B 18176 bytes
SHA-256: b971c5ee2eec0bf958612c61fefa7e745d85741e8be93a5ffe952fc5dee4e27b
font_01_sfnt_off00010ae9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AE9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012300.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12300 10712 bytes
SHA-256: dbcb5d644cd2f81a7cb0aca381afeed5bcd4b52bdbd3dd2ba8fc275358ae2bf4