Malicious PDF — malware analysis report

Static analysis result for SHA-256 f16bda39cc349909…

MALICIOUS

PDF

97.8 KB Created: 2021-07-14 06:16:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bf1df3dffa9a88bffb443ae6a462f29d SHA-1: 478311e2cd4233823247b2416a5def8286428ff4 SHA-256: f16bda39cc349909c8c8cae90a024222ca1ec17f584c9550f1752d905cd22c61
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple potentially compromised websites. The presence of 'curl of a field' in the document text, alongside numerous embedded URLs, suggests an attempt to manipulate search engine results or trick users into visiting malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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://jancsoalapitvany.hu/ckfinder/userfiles/files/78085617837.pdf
    • http://verdantnorwich.com/clients/3/30/306756bb587dffcd11ca74610d845a16/File/95406197253.pdf
    • https://nepalipublisher.com/ckfinder/userfiles/files/kakisedojujigixabol.pdf
    • https://ukdirectremovals.com/wp-content/plugins/super-forms/uploads/php/files/3ea7fb7e635eb24a99308700299c8217/50369350862.pdf
    • https://micro-logic.ro/images/uploaded/file/voxuxanigorara.pdf
    • https://luminex.pl/upload/file/8577491004.pdf
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/q7hhr4etgj7nk6g9uhmna3l0ep/89789688195.pdf
    • http://sodrex.pl/userfiles/file/93594053778.pdf
    • http://driver-jazda.pl/upload/file/vamixamikitusarewiv.pdf
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ecea27a209---94433812038.pdf
    • https://centrosteadycam.it/wp-content/plugins/super-forms/uploads/php/files/a89307fcc23c8d015f3f3119866ee5c0/nitotiso.pdf
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/2nhdac2fevfuqljtbsqt2sfbmr/4905208995.pdf
    • http://hnc2.com/userfiles/file/fisuwegok.pdf
    • http://tomaszfilipczak.pl/userfiles/file/43860457568.pdf
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/blfcfnh4ddah36mndvg0k0l0oe/kunifosekulewalivirefofe.pdf
    • http://fixafilm.se/userfiles/file/98320137852.pdf
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c152eee1209---jevura.pdf
    • https://jnfarley.com/wp-content/plugins/super-forms/uploads/php/files/1msjp2d87h5kviopiuten20g40/dalurovosonigasizazoxa.pdf
    • http://www.mezmat.ru/ckfinder/userfiles/files/94791841580.pdf
    • http://esoftland.com/userfiles/file/72021135711.pdf
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/cogvsl7727siitg8becm1oqnjv/88658334800.pdf
    • https://jancsoalapitvany.hu/ckfinder/userfil
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=curl+of+a+field
    • 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_off000100fa.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x100FA 16792 bytes
font_01_sfnt_off0001190c.bin
cca615d9b56063f33524626bf817a5b4a29c9434de1c442d62529d6c267ed9a8
pdf-font-stream PDF embedded font (sfnt) at offset 0x1190C 18956 bytes
font_02_sfnt_off00014c00.bin
38e6d1a790b6142bf497410e3d6c2d74eb744ac920c513bb577b2f64cf473a86
pdf-font-stream PDF embedded font (sfnt) at offset 0x14C00 16560 bytes
font_03_sfnt_off00016358.bin
35f8751837f226f7df77fe836687a7245d377d764dc338bf89ee379c55b93e8c
pdf-font-stream PDF embedded font (sfnt) at offset 0x16358 10108 bytes