Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b8b5d54a3cc261a…

MALICIOUS

PDF

72.9 KB Created: 2021-09-29 01:47:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d3f4c8ce7f0e47ea46271a6d3b4131cf SHA-1: 65441593b5214c4f5d5063cd517497c84d4f98fd SHA-256: 2b8b5d54a3cc261ad14ecc6c00991a3bedd76e2751c20ff527a02b4b5b7d962c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains a link farm pointing to multiple domains, some of which are hosted on compromised CMS platforms, suggesting an attempt to redirect users to phishing or malware download sites. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://hiddencliff.kr/FileData/ckfinder/files/20210917_AB072C13BC4F3062.pdf In PDF document text
    • https://doosradashak.in/ci/userfiles/files/subuvegisituvosekorut.pdfIn PDF document text
    • http://anneadamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/44274883850.pdfIn PDF document text
    • http://www.phuongdonggolf.vn/app/webroot/uploads/files/18065910966.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16145b1240446f---96335204606.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133c3cd93677---67902358634.pdfIn PDF document text
    • http://veganogle.es/uploads/ckfinder/files/72941477341.pdfIn PDF document text
    • http://gruaszarate.com/ckfinder/userfiles/files/39713987989.pdfIn PDF document text
    • http://baove24h.org/upload/files/xulax.pdfIn PDF document text
    • https://kibledergisi.net/resimler/files/58597163181.pdfIn PDF document text
    • http://saigonradio.com/userfiles/file/10632446737.pdfIn PDF document text
    • http://zvaracskaskola.eu/editor_uploads/system/files/buruke.pdfIn PDF document text
    • https://aalatour.com/basefile/b2caalatourcom/files/69043660711.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16130a5970120a---24666217552.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/2k4ev04o9emqbp2gqhstkmugaa/3232498774.pdfIn PDF document text
    • https://confidence-ist.com/ckfinder/userfiles/files/divemevawo.pdfIn PDF document text
    • http://agapetown.net/ckfinder/userfiles/files/jiwexikulozi.pdfIn PDF document text
    • http://colorfusion.us/admin/images/file/fiwifaninigirojodikinimef.pdfIn PDF document text
    • http://villaelen.it/userfiles/files/suloxugapiginekovisotegi.pdfIn PDF document text
    • http://travelci.ru/ckfinder/userfiles/files/74090253286.pdfIn PDF document text
    • https://fallsplat.se/bildbank/file/romojujamodaniguzuwi.pdfIn PDF document text
    • https://oykufestivali.com/ckfinder/userfiles/files/19165235480.pdfIn PDF document text
    • http://ambulatorioveterinarioilprato.eu/userfiles/files/gepod.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/xojesizotinileles.pdfIn PDF document text
    • https://medtek.vn/storage/file/71836840630.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=an+unquiet+mind+pdf+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_off0000b7e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7E1 10392 bytes
SHA-256: fc83a6273478d9d41d84bcf7d8822707b96c0cc030a6e7442e16be056a7e0df2
font_01_sfnt_off0000cf16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF16 18220 bytes
SHA-256: 6ba59220aa09181a42f7fba1db506057f3b4d104851bfd01a9caefcbd337357b
font_02_sfnt_off0000fdc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDC9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1