Malicious PDF — malware analysis report

Static analysis result for SHA-256 40023cd08ae82515…

MALICIOUS

PDF

96.3 KB Created: 2021-07-01 14:03:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 783586a92a966be77624058e6e43e2b2 SHA-1: 66554dee43b56c457c7e877f58805672e2119a11 SHA-256: 40023cd08ae825157c1e9635f8a31bab2c84dbe6096f1a33f813b714ee40df98
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to compromised WordPress uploads and other disposable hosting sites, likely for phishing or malware distribution. The embedded URLs and the nature of the link farm suggest an attempt to exploit user trust through deceptive content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://huntic.ru/uplcv?utm_term=questions+and+answers+for+christmas
    • http://colegiosantarosa.com/uploads/imagem/file/87207442596.pdf
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1675f82216---76845359524.pdf
    • http://vincentpopetutoring.com/clients/d/dd/dd6b7bcf94cac99d3bed97cf8166637b/File/66391381801.pdf
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/02f1d452c4e3dbc2d1f72ad45f1790fa/kadezudagetalasi.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/n1m6mf6u1ds1809s6u2jemioh1/79487436096.pdf
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/590822b338c0d573983db84a7e5555d5/60653534323.pdf
    • http://nenkin-t.com/upload_img/ck/files/91723709653.pdf
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d1475668a7---sozediketasobekigabu.pdf
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083ff449ceed---runalidijalu.pdf
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/3db7a1555d82377df49c6cc32ab2b8aa/15520581027.pdf
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072d3923a33a---kamusetur.pdf
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160cbd1e675993---90857180059.pdf
    • http://stsaischoolamritsar.com/slbdavbatala/userfiles/file/gamikupafoju.pdf
    • http://alemotta.com/resources/original/file/rekelofaxun.pdf
    • https://www.travelticket.com.au/wp-content/plugins/super-forms/uploads/php/files/d1cmu8l9up932gcolpokell5nj/15488975772.pdf
    • http://nusratali.com/userfiles/files/30206346878.pdf
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/r1u4qj40qph14p50a2iibhh2vg/robusezazaloxanokope.pdf
    • http://quadocdao.vn/uploads/files/tojinawal.pdf
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb6b748dd1f---23543224991.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160856841557b3---xujaxibegatinolej.pdf
    • http://sillajen.com/fckeditor/_upload/file/45484804396.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fe04.bin
fe9448583a05bd8002a6ff7b9d0fc4a9a9e18107411fc01a1f098e1ef9f435b1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE04 10940 bytes
font_01_sfnt_off00011759.bin
148691e139a42d7ca358c40d6d57122be8817ffeadd7641e309bee0dfeabfbab
pdf-font-stream PDF embedded font (sfnt) at offset 0x11759 16164 bytes
font_02_sfnt_off00012ceb.bin
bc65686a5ebbc5b68105536f763d6601d49ea0c7f66359dbcd25510e55d11242
pdf-font-stream PDF embedded font (sfnt) at offset 0x12CEB 17684 bytes
font_03_sfnt_off000159a7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x159A7 16792 bytes