Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2ca2ccf4df00098…

MALICIOUS

PDF

87.9 KB Created: 2021-07-20 00:04:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 04b31e2f7f1e6c0562460bf99a2ea466 SHA-1: ee9d7b5ff8596254684c9a7cb001e3acff1b5a3e SHA-256: a2ca2ccf4df000987bfa8abee172d86048b0b8195d03aa35ecfe592fe0fb17e4
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. Multiple heuristics indicate the PDF contains numerous external links, many pointing to compromised CMS upload storage or disposable hosting. The document body is heavily obfuscated, preventing analysis of its direct content, but the presence of these links strongly suggests a phishing or SEO manipulation scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 https://tomas-music.com/contents//files/xemifepefiv.pdf In PDF document text
    • http://brukbet.com/user_images/file/59944184264.pdfIn PDF document text
    • http://dancedynamicsla.com/clients/38740/File/36387282993.pdfIn PDF document text
    • http://m4klynchburg.org/clients/3/34/34420611de4c9c7593cf5e5fe12de6df/File/63649046253.pdfIn PDF document text
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/corsg1v5lv8n1e4776l4d5q0v6/neroxizurusojem.pdfIn PDF document text
    • http://flatadministration.com/uploades/fckeditorfile/vinotomosun.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b440a2b9b88---42393755284.pdfIn PDF document text
    • https://la-klamm.org/userfiles/file/pebile.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a18848a5127---debofapanewabalopu.pdfIn PDF document text
    • http://www.verneteco.com/ckfinder/userfiles/files/telumewemaforisurevepox.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608d69fe8ed05---34633818310.pdfIn PDF document text
    • https://arab-hams.com/Ups/files/81402004595.pdfIn PDF document text
    • http://puzynowska-kancelaria.com/userfiles/file/pirogumokibidikilumabofar.pdfIn PDF document text
    • http://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/36278127257.pdfIn PDF document text
    • https://acavacecio.it/userfiles/files/99739367985.pdfIn PDF document text
    • https://www.liftechforklifts.com.au/application/third_party/ckfinder/userfiles/files/23568450801.pdfIn PDF document text
    • http://www.onlinetemsilci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607de6c3836fb---saxixemimobilomokosegode.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/094acf527ae6882623bf66212f59abab/82002844227.pdfIn PDF document text
    • http://videoacceso.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4c9a926096---godele.pdfIn PDF document text
    • https://premium-house.uz/images/file/18348404885.pdfIn PDF document text
    • http://timebank.ru/sites/default/files/photos/pagefile/71328844186.pdfIn PDF document text
    • http://cyklo-sport-servis.cz/UserFiles/File/mosizixovidi.pdfIn PDF document text
    • http://dajuicebarus.com/uploads/files/tazojetigezujaxo.pdfIn PDF document text
    • http://kiavysocina.cz/UserFiles/File/83118203978.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=jack+all+trades+master+of+nonePDF 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_off0000f52c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF52C 10628 bytes
SHA-256: e631f4212e4bdbe189b39437eb6846a75b47da941df9871584133e5370e39fe1
font_01_sfnt_off00010d96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D96 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000125a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125A8 17212 bytes
SHA-256: 3b3735f0bd6c5c32a6bb2645fe936418691d5e877a0b9b52939be4d92a7031e0