Malicious PDF — malware analysis report

Static analysis result for SHA-256 b827891ac138c10e…

MALICIOUS

PDF

99.8 KB Created: 2021-08-20 21:17:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fe2f780dcf9022fcf1c6fe9d0527ce13 SHA-1: a23dcdd4a01a145ab3744c966c343394a3de5327 SHA-256: b827891ac138c10edbeab179a88124cafeec40b37e582e250a5a00a269e8a8f6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The file functions as a link farm, with numerous URLs pointing to compromised WordPress upload directories and other disposable hosting. These links likely serve as redirects to phishing sites or malware downloaders, aligning with the characteristics of a phishing or trojan distribution campaign. No scripts were extracted, but the structure suggests a spearphishing attachment used to lure victims to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adb82295ca7---9323716811.pdf
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160af893401371---boviromekux.pdf
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/e478b6174322ae7a480450da4e5f0d41/lufunefepumijex.pdf
    • https://calldidocta.com/wp-content/plugins/super-forms/uploads/php/files/52f6ceb1e33082f34c627947a7f188a9/netuniji.pdf
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1607a890dba18e---18272496522.pdf
    • http://dep14kirov.ru/userfiles/file/zupuwuvudamevepuviwiwar.pdf
    • http://ats-dz.com/userfiles/file/78207629261.pdf
    • http://westmoorclassof1965.com/clients/5/52/52ec68f2b927accf75267cb07bfcc891/File/28097226257.pdf
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609e3eb456d34---puponivelumu.pdf
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad122f6bd43---5484381278.pdf
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/309ffb73f22d939d435fe45fff206380/9955284440.pdf
    • https://mls.lighting/wp-content/plugins/super-forms/uploads/php/files/153943b39f6307379037fda5ff44f387/zowusubesagimem.pdf
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/c6cd055d7fa02e88cb37c80c91ebbe1a/47276037269.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609b1bf71c660---kivufopiwimedifun.pdf
    • https://alshamiltrading.com/alshamilfiles/file/wigugidosetexivuwi.pdf
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/d28cf290f8e5cb57c36c880c19c01bf7/roranafipege.pdf
    • http://www.mmd.ntou.edu.tw/ckfinder/userfiles/files/74828726102.pdf
    • http://mousike.it/img_ins/files/53814820242.pdf
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/do1e8je72m07b33f3c108e025r/nilapagugivapesobige.pdf
    • http://thingsantiquesla.com/userfiles/files/xitibobugumajejukikij.pdf
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/8c7f7b90dd4c4c3bf83a0e4cceb7bde4/61420311258.pdf
    • http://aaaexpressheating.com/userfiles/file/lajobefijejerarexipipe.pdf
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/0023bf9fc67eea7ca002d62dbe9144f5/dilifubiver.pdf
    • https://ckd-otto.com/contents//files/sigerared.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=manual+para+resolver+el+cubo+de+rubik+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_off00011c88.bin
ffcc8af95a981864a449b0fca84dbfcd35a363f2308ffb3464c387f304bd576f
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C88 10904 bytes
font_01_sfnt_off000135a7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x135A7 16792 bytes
font_02_sfnt_off00014db9.bin
a5bf2fa6ce45f9fa48eb7961e6024097cd729d07e1999553819e5df1f914fa99
pdf-font-stream PDF embedded font (sfnt) at offset 0x14DB9 19644 bytes