Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8387e5d5f58f4f5…

MALICIOUS

PDF

87.2 KB Created: 2021-09-23 10:00:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 3c5149b7b2fc2775d9e5c0e4d30e79f5 SHA-1: 9c4f3364f2b1240a7df036abf30584b0da6ca206 SHA-256: f8387e5d5f58f4f55e4a61a207471ef50fc2f88a3bcea4faf614427b162f0e11
156 Risk Score

Malware Insights

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

The PDF document was flagged by multiple heuristics, including ClamAV and an ML classifier, indicating malicious intent. It contains a link farm pointing to various domains, some of which are identified as compromised CMS uploads, suggesting a phishing or malware distribution scheme. The presence of external URIs and link farms indicates an attempt to redirect the user to external resources.

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 http://www.biharikft.hu/bihari-admin/ckfinder/userfiles/files/sobevemozifabuzodagu.pdf In PDF document text
    • https://defrokatilai.lt/images/files/93449303712.pdfIn PDF document text
    • http://ljjxmining.com/uploadfile/file///2021092305120348.pdfIn PDF document text
    • http://outspokenholland.com/userfiles/fckFile/20210922224941.pdfIn PDF document text
    • http://swissies.lt/ckfinder/userfiles/files/92916152945.pdfIn PDF document text
    • http://koreaseals.com/ckfinder/userfiles/files/43566711069.pdfIn PDF document text
    • https://icicle-mountaineering.ltd.uk/ckfinder/userfiles/files/lagigiwitipita.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/fbd8a6fa0c289a981d55fae708dd316e/sijabajok.pdfIn PDF document text
    • http://digifast.cz/userfiles/migofegosusozebu.pdfIn PDF document text
    • http://nhakhoauytinhaiphong.com/upload/files/jusanapopupuvuvakixaza.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1613b498e2972a---51946719646.pdfIn PDF document text
    • http://fishtech.org/uploads/userfiles/file/file/fowibukovone.pdfIn PDF document text
    • http://www.lukoilmarine.com/ckfinder/userfiles/files/54461968046.pdfIn PDF document text
    • http://orderleesushi.com/uploads/files/35497149166.pdfIn PDF document text
    • http://issaproject.com/app/views/panel/ckfinder/userfiles/files/72113204479.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/02bafe665598d3c0e7045fd4b3762921/20721463946.pdfIn PDF document text
    • https://kopari.hu/files/file/5524856489.pdfIn PDF document text
    • https://crcnueva.naturasoftware.com/uploads/images/files/nowokixunelapufunu.pdfIn PDF document text
    • http://mt-filtration.com/uploaded/file/2363309686134619549138.pdfIn PDF document text
    • https://tl-systems.hu/files/files/devopadanoletiniw.pdfIn PDF document text
    • http://cc-loges.com/uploads/file/latana.pdfIn PDF document text
    • https://kozlovka.mebel18.com/uploads/files/gefit.pdfIn PDF document text
    • http://milkyway-vn.com/upload/files/15003779757.pdfIn PDF document text
    • https://djecijagarderoba.me/userfiles/file/bokef.pdfIn PDF document text
    • http://ouhkpthaa.org/userfiles/rexilusadagapukasizuvi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=genshin+buy+primogemsPDF 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_off0000efd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000107ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107ED 10788 bytes
SHA-256: 1100391da4a55990558755c72c01abae253c330189e3b58a56b41d0ab228651f
font_02_sfnt_off0001205d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1205D 18204 bytes
SHA-256: 2e78a15dd147e45ca7895eaa890d4a0287eb3121cdd69fbb82773ecc308738a8