Malicious PDF — malware analysis report

Static analysis result for SHA-256 2147c236f25e4d3e…

MALICIOUS

PDF

85.8 KB Created: 2021-09-22 13:50:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 93632f54f6ebf2ac4414385edd2d70dd SHA-1: 0b54ce06e12bb4442d3274cfee75ea8c8edc1a39 SHA-256: 2147c236f25e4d3e4bb3e2bc4a016a51291d141ac148b8612789c5fcae160cb2
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a PDF link farm, with many embedded URLs pointing to potentially compromised websites or disposable hosting. The primary attack pattern involves luring users to these external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/9609233b757eee0b311426fe96cdcb21/jadovuram.pdf In PDF document text
    • https://g4m3s-4p1-12s1.com/contents/files/2543854831.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/frntv9m2ar373cujsot20411op/numiwovewudo.pdfIn PDF document text
    • http://frutapac.com/ckfinder/userfiles/files/56520135684.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139a268a5e2c---23793644779.pdfIn PDF document text
    • https://tskrea.com/userfiles/file/69891884818.pdfIn PDF document text
    • https://efnnma.org/files/file/15230032116.pdfIn PDF document text
    • https://fablab808.com/nbloom/fckuploads/file/35050250893.pdfIn PDF document text
    • https://icicle-mountaineering.ltd.uk/ckfinder/userfiles/files/14500962176.pdfIn PDF document text
    • https://inprovitecuador.com/ckfinder/userfiles/files/jatemavolunewu.pdfIn PDF document text
    • https://tsegypt.com/file/49416563402.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/etuzutatigopijivux.pdfIn PDF document text
    • http://velomagazin.hu/UserFiles/file/41286377291.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613e85a445111---40021411721.pdfIn PDF document text
    • http://plaschke-partner.com/uploaded/file/73479608808.pdfIn PDF document text
    • https://easternresources.net/ckfinder/userfiles/files/wilalinimefifimerigezob.pdfIn PDF document text
    • https://avukat.kocgrafik.net/upload/files/58726503167.pdfIn PDF document text
    • http://e5tbr.alruaa.com/ckeditor-ckfinder-integration/uploads/files/57167097046.pdfIn PDF document text
    • https://tresonance.org/uploadfiles/54737398378.pdfIn PDF document text
    • https://aprilboya.com/userfiles/file/wefewemafelesupuzoje.pdfIn PDF document text
    • https://lesartsdansmonjardin.com/userfiles/file/20210912194225.pdfIn PDF document text
    • http://canhtoanland.com/upload/files/43794582330.pdfIn PDF document text
    • https://aiwatopup.com/ckfinder/userfiles/files/bevovazuxogeseraxobufi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=katherine+to+timber+creekPDF 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_off0000ec1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC1C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010433.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10433 10504 bytes
SHA-256: 20114e8da58803c391e8bdcb6dab83cecb0331cf8fc40edd32f8109528fd6330
font_02_sfnt_off00011be0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BE0 17632 bytes
SHA-256: d58e5ec2e5cdf337d3e715fe7c446208131cd27448b3cb2dd682773a01c1de65