Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fe067b31bf9ac66…

MALICIOUS

PDF

80.6 KB Created: 2021-09-16 16:33:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 92bf6457d182f6429fb61ad01ad7faa9 SHA-1: 4ce1e9975193421f97cbc63a47bf97e135a5de72 SHA-256: 8fe067b31bf9ac66f3ac9b93a76e37016ab85c28826c10a03672467f9461b695
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. While no scripts were explicitly extracted, the nature of the links and the ML detection indicate a high likelihood of malicious intent, possibly involving JavaScript execution or exploitation of PDF vulnerabilities to achieve its goals.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://mayphoviet.com/media/ftp/file/36044694437.pdf In PDF document text
    • http://steinemann-ag.ru/wozufigis.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/0c8747c27d6518cabda3a883dbd50bc6/91212041063.pdfIn PDF document text
    • http://www.ciesol.es/ckfinder/userfiles/files/tepelaje.pdfIn PDF document text
    • https://djecijagarderoba.me/userfiles/file/85509711246.pdfIn PDF document text
    • https://calprin.com/ckfinder/userfiles/files/folikerobixisubemanixig.pdfIn PDF document text
    • http://pro-group.ru/userfiles/files/81720934380.pdfIn PDF document text
    • http://www.jasolasia.com/image/upload/File/19701388509.pdfIn PDF document text
    • https://btsis.com/upload/ckfinder/files/50545101404.pdfIn PDF document text
    • http://motovelo-nmsk.ru/userfiles/file/buzakebag.pdfIn PDF document text
    • http://kovacsoltvaskerites.hu/images/file/sotukofese.pdfIn PDF document text
    • http://fu-xin.tw/uploads/files/202109040759231835.pdfIn PDF document text
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/1d4a6a3892a0d23dbecaee5245320998/xogexeviwesimomusovul.pdfIn PDF document text
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613c9a2d6a87a---jexugif.pdfIn PDF document text
    • http://prime42.ru/userfiles/files/35825791224.pdfIn PDF document text
    • http://sutipatika.hu/userfiles/files/72213423209.pdfIn PDF document text
    • http://csa.china-led.net/static/editor/ckeditor/ckfinder/upfile/files/zenozavikemabikodal.pdfIn PDF document text
    • https://askisan.com/upload/ckfinder/files/40361477788.pdfIn PDF document text
    • http://1night2daytour.com/ckupload/files/janasiralepele.pdfIn PDF document text
    • http://le-bouquet.be/userfiles/files/zerulage.pdfIn PDF document text
    • http://indago-rovigo.it/userfiles/files/10487705286.pdfIn PDF document text
    • https://sskundal.com/userfiles/file/1796657789.pdfIn PDF document text
    • https://fsreloading.com/userfiles/files/ritibujekifuvuwujaz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=what+do+the+symbols+on+the+top+of+my+phone+meanPDF 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_off0000d816.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD816 17076 bytes
SHA-256: f1e8738e38e0895919e14b429c23f8b250eac27472a37393382289712ebd3b1e
font_01_sfnt_off0001040f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1040F 10816 bytes
SHA-256: 477418d2ee05151d127ab30397197056e25139b21cb62f1c96074d0ce2a4644a
font_02_sfnt_off00011ca0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CA0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1