Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f45d34e56c7decf…

MALICIOUS

PDF

78.3 KB Created: 2021-09-03 14:34:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: dc3f0e228026a09497ef0e2cadb239f1 SHA-1: ff87bda561a9ec381f5b6e1258f3e9c657c001bd SHA-256: 8f45d34e56c7decfe170cc4716e7e73a3e49820118a3527b2172638859ffa727
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. Heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest this malicious intent. ClamAV detection and the ML classifier further confirm its malicious nature, likely serving as a phishing lure or a distribution point for further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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.aqsclimited.com/EditorImages/file/96845976139.pdf In PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae3c3fc7928---93742827222.pdfIn PDF document text
    • http://xn--b1akwe.xn--p1ai/userfiles/file/48687411656.pdfIn PDF document text
    • https://phunhai.net/upload/files/kobobikub.pdfIn PDF document text
    • http://hanarotalk.com/userfiles/file///28127883694.pdfIn PDF document text
    • http://zxpgw.com/userfiles/file/posupedoxidulipomerixur.pdfIn PDF document text
    • http://michaelwilliamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/diketa.pdfIn PDF document text
    • http://bbmeti.it/userfiles/files/valiritevasuwani.pdfIn PDF document text
    • http://prabashproperties.com/ckfinder/userfiles/files/balutupar.pdfIn PDF document text
    • https://baodinhsolar.com/wp-content/plugins/super-forms/uploads/php/files/h9vbnv6mou2nrtv8tl7rp9dsic/napigazafafibukivese.pdfIn PDF document text
    • https://latework.cz/soubory/gutanafebewotedar.pdfIn PDF document text
    • http://seabeachthailand.com/UserFiles/file/24545952269.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/586eabdbe9540b999b0730002db6c4f4/3321799377.pdfIn PDF document text
    • http://megalaserasia.com/upload///5942907479.pdfIn PDF document text
    • http://stpatricksreunion.com/clients/84553/File/zedonedebedilajo.pdfIn PDF document text
    • http://bakefruit.com/uploads/files/202108270017534584.pdfIn PDF document text
    • https://holyfamilyhospitals.com/ckfinder/userfiles/files/bagimadibado.pdfIn PDF document text
    • http://ridendo.cz/files/file/85530782427.pdfIn PDF document text
    • https://sunnyrosesschool.com/userfiles/file/47924620809.pdfIn PDF document text
    • https://anpheatingandac.com/nbloom/fckuploads/file/satabarelepudamaminulusot.pdfIn PDF document text
    • http://runnersavezzano.it/public/userfiles/file/farezokamubonov.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=cursive+alphabet+handwriting+worksheets+freePDF 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_off0000cbc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBC5 17588 bytes
SHA-256: 9bf23d4a5d6a4fbbee4676ce123445ba118678e1daba001232fc11af68dae0b9
font_01_sfnt_off0000f919.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF919 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011130.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11130 11292 bytes
SHA-256: f593801f77ac74bb0a0a6177c8accd3d1264dc843b9d9fa441f8a36ae3d378ba