Malicious PDF — malware analysis report

Static analysis result for SHA-256 84ce4d81cf9e9a98…

MALICIOUS

PDF

69.5 KB Created: 2021-07-10 04:50:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cb3d4946b4613afc3d1d1394e40db1e6 SHA-1: 9c2cbde62c06944e226e91148b138a827e44bcf5 SHA-256: 84ce4d81cf9e9a98cff46c6c1c9bf72eb94e128d9d370f7c1e1633ed871617be
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file is identified as malicious by ClamAV and ML classifiers, exhibiting characteristics of a phishing lure. Heuristics indicate it's an image-only document with clickable action triggers, designed to redirect users to various external URLs, many hosted on compromised CMS platforms. The document body is heavily obfuscated and unreadable, suggesting it contains no user-facing content and serves solely as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 69 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://hnkingdee.cn/Files/file/2021527395.pdf
    • http://sunnysideclassof64.com/clients/a/ac/acc4ccb49d7935ca36198347b895393e/File/24643502649.pdf
    • https://serwisnawigacji.pl/userfiles/file/49340131118.pdf
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160926a1564a6d---61415661302.pdf
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/m7vk2f77fn38rfuoqir10880g9/taxadov.pdf
    • https://eventaipei.com/upload/files/tonevufedeb.pdf
    • https://accuratesearch.com/userfiles/file/xamaxarigo.pdf
    • http://aromaonly1.com/yamituki-n/uploads/files/pifeg.pdf
    • http://bjhtdszdh.com/v15/Upload/file/2021662025208887.pdf
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfa7f82f297---vasozadeg.pdf
    • http://juniorsmagazine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b28fae1e6f---27775491902.pdf
    • http://kanstm.com/ckupload/files/81212806303.pdf
    • https://apoiotelecom.com/imagens/img_fckeditor/file/51683529384.pdf
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/2e4580988734e145257a7e6e056df21f/55437895799.pdf
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c5211caf252---zevotuj.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160adaafeaffa5---lilavasikezowojukemuzagun.pdf
    • https://www.alignerco.ca/wp-content/plugins/super-forms/uploads/php/files/a5fb5f90f5a72a8d961f18ff49c0ca77/40049887441.pdf
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/16075ecb767852---xevuketekefiwoxedalilu.pdf
    • http://e-hematologica.com/users//file/lipupolijolibajoko.pdf
    • http://westleyden72reunion.com/clients/4/46/469dc9162705cbff2d1fbe132f144f37/File/69669557351.pdf
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/160913533781ff---31129823090.pdf
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5a368fc61---naxomivuxivu.pdf
    • http://xn--80aaeiengkwpz6p.xn--p1ai/pub/file/jepekumoxukimuton.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=telugu+two+letter+words+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b760.bin
359b8b763a5ca176380b9e833cd71a145ea50a3a8e4064ebf88d6f642ccf14c4
pdf-font-stream PDF embedded font (sfnt) at offset 0xB760 10464 bytes
font_01_sfnt_off0000cf28.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCF28 16792 bytes
font_02_sfnt_off0000e73a.bin
d638f0a4b7e40e5b63e87bb5442d2e4f789f1593b74a9e44fca8ee2174886c54
pdf-font-stream PDF embedded font (sfnt) at offset 0xE73A 13612 bytes