Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf7fa1aca7cf9f87…

MALICIOUS

PDF

70.9 KB Created: 2021-09-16 11:11:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 77398e93d888d66c172e0d6bef810d31 SHA-1: 6323bf238b9953a7c4a997589c0fa631581f0c56 SHA-256: bf7fa1aca7cf9f87b574c8a5a864413b4429f44c7fd10d9d2771a38ecdbc05a4
156 Risk Score

Malware Insights

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

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier as malicious. It contains numerous links to compromised WordPress upload storage and other disposable hosting, indicating a link farm designed to redirect users. The presence of these links suggests an attempt to distribute malicious content or phish credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/an11t18ek87c6m0mjv63ft4vo2/madusitagolu.pdf In PDF document text
    • http://vitali-schulz-eiskunstlaufen.de/userfiles/files/silelarujagup.pdfIn PDF document text
    • http://doingthing.com/downloads/blog/geust/files/96032317365.pdfIn PDF document text
    • http://win-sonic.com/ck_imgs/files/85050856210.pdfIn PDF document text
    • http://onlinetradeshow.ir/uploads/files/4056100231.pdfIn PDF document text
    • http://majstrissmt.eu/www-data/file/liwubesupol.pdfIn PDF document text
    • https://affordans.com/ckfinder/userfiles/files/ronagezupu.pdfIn PDF document text
    • https://yk-tech.com.tw/ckfinder/uploads/ckfiles/files/pinenifefazuruzukiwe.pdfIn PDF document text
    • https://vibangnhadat.com/uploads/files/kulukikoxasewexojo.pdfIn PDF document text
    • https://charterfori.ir/basefile/charterforiir/files/93952842786.pdfIn PDF document text
    • http://musicpark-live.de/userfiles/file/57032360984.pdfIn PDF document text
    • http://bjdfszwy.com/filespath/files/20210916122455.pdfIn PDF document text
    • http://www.moyekolodin.com/files/84961380309.pdfIn PDF document text
    • http://www.ktgroup.co.uk/ckfinder/userfiles/files/nuxukuwuborapixozax.pdfIn PDF document text
    • https://hotararicedo.ro/files/files/webunimexevevutuvonov.pdfIn PDF document text
    • https://websbag.com/uploads/files/befokakasok.pdfIn PDF document text
    • http://patanjali.zohukum.com/ckfinder/userfiles/files/pojixif.pdfIn PDF document text
    • http://transportdiverse.com/uploads/files/gesimokuniredudibupafawik.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140c1885c25f---54962582127.pdfIn PDF document text
    • http://yearbookplus.com/uploads/ckfinder/files/bawanapepewebifufedol.pdfIn PDF document text
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/r2d88brkrdjm5ql27a21k3ntgi/letatu.pdfIn PDF document text
    • https://delaneyllc.com/ckfinder/userfiles/files/xelenifalexowagaji.pdfIn PDF document text
    • http://mosme.org/uploadfile/files/55667576206.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=coc+mod+apk+clash+paradisePDF 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_off0000b47a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB47A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC91 10700 bytes
SHA-256: 57ae1769c15f97cf20e160b156fe50f02464496d4f28d6fe34ca3df1118302c5
font_02_sfnt_off0000e516.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE516 16156 bytes
SHA-256: f9e612d1d2fb3848748b3b84a113714bd136ee3747b248963c1738169d435e17