Malicious PDF — malware analysis report

Static analysis result for SHA-256 39b3730da3957418…

MALICIOUS

PDF

82.9 KB Created: 2021-09-12 03:16:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4a9bbd077ef04124a3f4acf6f147d4b5 SHA-1: 565aa065f47d13cd397a0c6044c574e3a02664d6 SHA-256: 39b3730da39574189c24684346f76106e33be3231b1cc8d10ee913ece6c42db9
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicating a high number of distinct hosts and links, suggesting a redirection scheme. ClamAV detection and ML classification confirm its malicious nature, likely as a phishing or malware delivery mechanism. No scripts were extracted, and the document body was unreadable, limiting further analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://pilot-nav.com/ckfinder/userfiles/files/5440399167.pdf In PDF document text
    • https://hoatuoi360.vn/uploads/files/vesigizeta.pdfIn PDF document text
    • http://arohitourandtravels.com/userfiles/file/8313567821.pdfIn PDF document text
    • http://ilyxrace.com/userfiles/files/29344953493.pdfIn PDF document text
    • http://matras-devison.ru/upload/file/60471789232.pdfIn PDF document text
    • https://magnettoptan.com/upload/ckfinder/files/52673726241.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/jutifawevetigeduxuvo.pdfIn PDF document text
    • http://kaithompson.com/userfiles/file/tesolani.pdfIn PDF document text
    • http://dongduong.net/Images_upload/files/38556788507.pdfIn PDF document text
    • https://eliteplacementagency.com/uploads/files/mewododefurigiridolona.pdfIn PDF document text
    • https://geloracinta.com/contents/files/munarupoxusevuwewovopax.pdfIn PDF document text
    • http://tianlanip.com/filespath/files/20210909040331.pdfIn PDF document text
    • http://personal.sut.ac.th/chantira/port/ckfinder/userfiles/files/72380105465.pdfIn PDF document text
    • https://computerzone.pk/file/fatazi.pdfIn PDF document text
    • https://wangwangcamp.com/uploads/files/202109080619325931.pdfIn PDF document text
    • http://streetnn.ru/data/upload/ck/files/47546493848.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd518e0e07---tozemugigefozavevat.pdfIn PDF document text
    • https://chungangroup.com/uploads/files/202109062226153407.pdfIn PDF document text
    • http://xn--82cac8d3ajrc0gd0bo4a7nf3qg.com/userfiles/files/39366468974.pdfIn PDF document text
    • https://alasclub.gr/neuro/ckfinder/userfiles/files/3199220380.pdfIn PDF document text
    • http://randygordonlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/31939233136.pdfIn PDF document text
    • http://vuonlan.vn/data/upload/files/35851499377.pdfIn PDF document text
    • https://muzpony.de/obrazki/file/togiwiwisopudilazov.pdfIn PDF document text
    • http://travelport.pl/userfiles/file/jatij.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=android+tv+7.1+isoPDF link annotation
    • https://www.thc.gda.pl/ckfinder/userfiles/files/47452609125.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_off0000de72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE72 10116 bytes
SHA-256: 5611f87c27f19e9bc7d748f96580cd4a7f4b2f22d3febd7c551e3fe3947eb21d
font_01_sfnt_off0000f533.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF533 18644 bytes
SHA-256: a3f597009aaebdd11bbd3398f8445cead57fc3e0ed9316eb17420a4666dc212b
font_02_sfnt_off000125dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1