Malicious PDF — malware analysis report

Static analysis result for SHA-256 be8af507be7f4e62…

MALICIOUS

PDF

71.3 KB Created: 2021-09-21 01:37:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1550abf137f122dbaccdb95c151b4306 SHA-1: dafac996ec709172e650e4c87d5f11c4f452d346 SHA-256: be8af507be7f4e6208d59054364f767f3158a08ee2fc47051a3a10a6cf06b865
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristic analysis revealed it functions as a link farm, embedding a large number of external URIs, many of which are hosted on disposable domains. This suggests the document is designed to redirect users to potentially malicious websites, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure itself facilitates the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://huntic.ru/uplcv?utm_term=brisbane+casino+opening+hours PDF link annotation
    • https://motelandratecuci.ro/userfiles/file/31331832532.pdfIn PDF document text
    • http://xn----ctbguteehkho5h.xn--p1ai/ckfinder/userfiles/files/jubejaxuwuxini.pdfIn PDF document text
    • http://siamsankyo.com/Uploads/file/64822142576.pdfIn PDF document text
    • http://phdpecs.hu/userfiles/files/65249164255.pdfIn PDF document text
    • http://slbreakingnews.com/ckfinder/userfiles/files/20998655876.pdfIn PDF document text
    • http://okeefesreef.com/ckfinder/userfiles/files/vuvutivaxiladadejunajanis.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/1613f75e291103---87356021741.pdfIn PDF document text
    • https://helicopterleasingservices.com/userfiles/files/noranenetabovosexat.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613229748057f---muxumegisox.pdfIn PDF document text
    • https://corpeverest.com/ckfinder/userfiles/files/jubafewezobaro.pdfIn PDF document text
    • https://toppelletmachine.com/d/files/lixedu.pdfIn PDF document text
    • http://musicpark-live.com/userfiles/file/kumenolabokebinaf.pdfIn PDF document text
    • http://rcp-ranstadt.us/files/pokofotedebanapo.pdfIn PDF document text
    • http://thaisomboonautopart.com/userfiles/files/61449913681.pdfIn PDF document text
    • http://maasmartcity.com/userfiles/file/36126286255.pdfIn PDF document text
    • http://liweisteel.co.th/ckfinder/userfiles/files/dujugowogezujivefeximel.pdfIn PDF document text
    • http://www.yankey.com.tw/demo/public/editor/ckfinder/upload/user_upload/files/rererukebudoruvumewan.pdfIn PDF document text
    • https://www.edm-medical.net/ckfinder/userfiles/files/labulebogigafolukezixutir.pdfIn PDF document text
    • http://uzks.hr/upload/datoteke/werupizulonogawawafe.pdfIn PDF document text
    • http://nhakhoasaigonkimcuong.com/uploads/images/files/50673771883.pdfIn PDF document text
    • https://pavillonwohlen.ch/userfiles/files/potosuxevukunipewesuxosot.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/99080539496.pdfIn PDF document text
    • http://ensky-chemical.com/upload/files/jijojoto.pdfIn PDF document text
    • http://ordineveterinarireggioemilia.it/userfiles/files/xepopatekofitumudobi.pdfIn PDF document text
    • http://ecohost.ru/pics/images/file/juxawapimajufanujif.pdfIn PDF document text
    • https://amatnieks.lv/pictures/image/35613531142.pdfIn PDF document text
    • http://kccmaul.com/files/files/kirebudowiputifelol.pdfIn PDF document text
    • 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_off0000b6c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6C3 15740 bytes
SHA-256: e896fa1d85c026b92fd3d078e0bc26736c783a796b099be095a0af214af04c15
font_01_sfnt_off0000deeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEEB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f702.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF702 10804 bytes
SHA-256: 17158f288fc7fbed63d593cbaaf698a92b5c9d12afa0052eb0ba82268835cf48