Malicious PDF — malware analysis report

Static analysis result for SHA-256 823ca647cab1dd19…

MALICIOUS

PDF

75.0 KB Created: 2021-09-08 06:04:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: df4dfb52c6d67a59ba56d758459bdc6c SHA-1: affbbc1debe8ba3aca92327b1dd7ff9dcc52b3a7 SHA-256: 823ca647cab1dd1921eeda0a08c9a9da284e83e6b1b6d97e2295f4b8dbd7b6a2
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to potentially compromised websites or disposable hosting. The presence of multiple links, including one hosted on a compromised CMS upload directory, suggests an attempt to direct users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://artospace.com/pics/file/28863031752.pdf In PDF document text
    • http://bandenplaats.nl/cmsimages/file/mokomuxapozobuwolum.pdfIn PDF document text
    • http://burchiellati.com/file_fck/file/45497055001.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609762c0514c2---sowofapafoxejuvux.pdfIn PDF document text
    • http://brooklinehs1964.com/clients/6/6a/6a3559cec3eb17f551da2d864c8c85ab/File/9487658583.pdfIn PDF document text
    • https://hometeamcorp.com/images/usr/19980820663.pdfIn PDF document text
    • http://unionzglobal.com/ckupload/files/fikipujirujed.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/9c63180dec384a1bff92ef19cc5b1157/wafeluwexorupolesalub.pdfIn PDF document text
    • http://ikhmongol.mn/ckfinder/userfiles/files/lilikozixade.pdfIn PDF document text
    • https://svltv.in/userfiles/files/8743484505.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160855f1fd951f---94065132975.pdfIn PDF document text
    • http://jatyn.cn/upfiles/202106/file/1623758284.pdfIn PDF document text
    • http://dentalclinicbangalore.com/uploads/giwigazob.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/8cm57puegraie5v7qb0nc7ntqb/27827966637.pdfIn PDF document text
    • http://bradhelferlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fisozewabuvid.pdfIn PDF document text
    • https://vatlieutaphu.com/upload/files/99008235665.pdfIn PDF document text
    • http://medicalproduct.hu/images/files/zobedudizawuwofe.pdfIn PDF document text
    • http://elitsatodorova.com/uploadfiles/file/lenufemisod.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f73e6ac6fd---lafoxesiluturupaxurugetok.pdfIn PDF document text
    • http://www.vegagastro.pl/upload/file/98303313273.pdfIn PDF document text
    • http://bkht.vn/userfiles/file/kolejaxokisunufegexogiso.pdfIn PDF document text
    • http://soldresold.com/Shradhdha-Mehra/soldresold/final/ckeditorimage/files/fevotulapizi.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-6-24/20210624053101691653.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=ipsas+17+property+plant+and+equipment+pdfPDF 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_off0000c28f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC28F 16440 bytes
SHA-256: 4b1429d5d2a5cdc32cf4f883ffdfbb8b41802c9a8339d1851a65fc1e60884200
font_01_sfnt_off0000ece0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECE0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000104f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104F7 11072 bytes
SHA-256: 5ef69fe7bc37b01df2bf774fce1d88f854c3a3b9f9404e17335bde2cfb7c16da