Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8a8323b88dd87d0…

MALICIOUS

PDF

80.6 KB Created: 2021-09-22 15:27:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 81e0317ff8d37bd521737bb6f1ba2882 SHA-1: 4fc0fd5e56f79e70e95234c2ed326a56ff377f2f SHA-256: f8a8323b88dd87d097ac00f7cf950b8df60a30db8d271eeb5f817afd3bbaf538
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as 'Pdf.Phishing.Trojan' and by an ML classifier as malicious. It contains embedded JavaScript and numerous external URIs, many of which are structured as link farms on disposable hosting. The presence of JavaScript suggests an attempt to execute malicious code within the PDF viewer, likely to download or redirect the user to further malicious content. The overall structure and URL patterns indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=piano+learning+book+in+marathi+pdf PDF link annotation
    • http://telegid.tv/userfiles/file/gugep.pdfIn PDF document text
    • http://sanzmendia.com/userfiles/files/mowedepekorutafizetiliv.pdfIn PDF document text
    • https://olterus.org/contents/files/kemubosinitedamenufudasun.pdfIn PDF document text
    • http://expertsystemgroup.com/file_media/file_image/file/58729261715.pdfIn PDF document text
    • http://sadiqandsons.com/userfiles/files/30183206224.pdfIn PDF document text
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/sghkcgnp8umisdchuqevmc00k7/89302644132.pdfIn PDF document text
    • http://dlevitin.ru/fck_editor_files/files/53575225921.pdfIn PDF document text
    • https://chachachat.info/js/ckfinder/userfiles/files/21479381984.pdfIn PDF document text
    • http://fosterfreezesantarosa.com/uploads/files/xawerigovizubiwewujaji.pdfIn PDF document text
    • http://sport-zavora.cz/data/file/rinerojizuwo.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/gawaje.pdfIn PDF document text
    • http://westfallassociates.com/documents/file/76371407285.pdfIn PDF document text
    • https://noddy.nu/images/file/13283247221.pdfIn PDF document text
    • http://inimtrento.it/userfiles/files/mamale.pdfIn PDF document text
    • http://marchmontnews.com/imgs/file/64675548079.pdfIn PDF document text
    • http://ngor2-3.com/file_media/file_image/file/fodagubonizimatidu.pdfIn PDF document text
    • http://dentalclinicbangalore.com/uploads/fupitexavakulavefu.pdfIn PDF document text
    • http://xn--80aafbladvtgxneccoge3bt.xn--p1ai/pict/file/lapazofewu.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145c60db829b---fizapumu.pdfIn PDF document text
    • http://boras-sjuharad.boj.se/uploads/userfiles/files/64764954974.pdfIn PDF document text
    • http://ain.proximeo.com/ckfinder/userfiles/files/pubodivexuwojo.pdfIn PDF document text
    • http://xn--80aaffebba2apgigwiiececnggk9e4k.xn--p1ai/pict/file/39296017125.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/wexawitedujalumisib.pdfIn PDF document text
    • https://mabuksusu2.com/contents/files/64177217183.pdfIn PDF document text
    • http://macabrey-luthier.fr/data/Files/zuxixug.pdfIn PDF document text
    • http://abwingsva.com/uploads/files/86028618430.pdfIn PDF document text
    • 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_off0000d775.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD775 17048 bytes
SHA-256: b6375d573487d71154949b364ee8a535072f80470554a5708d123be9a62279fa
font_01_sfnt_off00010312.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10312 11008 bytes
SHA-256: 78c393e40550968955609827c2d32fd76950193c4210a6408ef5688ffb9f4108
font_02_sfnt_off00011c00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C00 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1