Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f1abc2cc43af7c2…

MALICIOUS

PDF

95.6 KB Created: 2021-09-24 02:31:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b81f8cd37d2fb188193c948726071783 SHA-1: d3911a2b9f538e5a1a13f36c0983bd87bba5cf74 SHA-256: 8f1abc2cc43af7c2adf732f2acd9bd6ac2251903008b1b3b23b42609d95039ad
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised CMS upload directories, suggesting it's part of a link farm designed to redirect users to potentially harmful content. The presence of multiple unknown URLs further supports this phishing or SEO poisoning attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614cce3c46f72---28054107343.pdf In PDF document text
    • http://wine-paraphernalia.com/files/winep/_repo/file/78385054139.pdfIn PDF document text
    • http://aptekarynek.pl/zdjecia/fck/file/33478298913.pdfIn PDF document text
    • http://centreforeffectivecoaching.com/media/file/ziwubideni.pdfIn PDF document text
    • http://cartopack.be/Images/file/81712029891.pdfIn PDF document text
    • https://smartstone.ca/userfiles/files/46983941606.pdfIn PDF document text
    • http://www.marcelasemper.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614161ffddcae---23635867240.pdfIn PDF document text
    • https://cqc-material.com/app/webroot/userfiles/files/29082147577.pdfIn PDF document text
    • http://rc-mst.com/mst/_upload/files/24028073294.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/c45bd02efd577096cbdb51c36af316df/73239519927.pdfIn PDF document text
    • https://technoarc.net/userfiles/file/44528224682.pdfIn PDF document text
    • http://tinhdauvietnam.vn/upload/files/55180915975.pdfIn PDF document text
    • http://gleb777.com/fck_upload/file/fezawuwubuwujibujuwujogoz.pdfIn PDF document text
    • http://ty6600.com/userfiles/file/bipegufapa.pdfIn PDF document text
    • https://ccskin.com/geektic/files/mofofa.pdfIn PDF document text
    • https://associazionemusicaviva.it/uploads/file/26071012396.pdfIn PDF document text
    • http://dekoblickfang.de/userfiles/file/vikefebesuveziruzifosamen.pdfIn PDF document text
    • https://rwd1.thadv.com/upload/files/52782863131.pdfIn PDF document text
    • http://traiteur-ribot.fr/userfiles/file/tutekuveposugekigixubo.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/16139bc9854a2a---1142784307.pdfIn PDF document text
    • https://doublehair.center/upload/ckfinder/files/97930389977.pdfIn PDF document text
    • http://kwiatmetal.pl/userfiles/file/badozudi.pdfIn PDF document text
    • https://almoheetmanpower.com/public_html/userfiles/file/39984845105.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=free+scores+pianoPDF 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_off0001108f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1108F 10200 bytes
SHA-256: 21daf353127978726eedc695983fca834e5185910a574068bc8306ad4653a2a1
font_01_sfnt_off0001277e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1277E 19048 bytes
SHA-256: e524a5026d64107df8689d3fc23f8bf9327fbe1b4e8dd455a0b9c3490eb9fa0a
font_02_sfnt_off00015923.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15923 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1