Malicious PDF — malware analysis report

Static analysis result for SHA-256 63de1cb4ff369f40…

MALICIOUS

PDF

84.7 KB Created: 2021-09-13 10:36:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2505cd7f2999fd6799f4df6c0f8b7253 SHA-1: 35b602f21b3c4e27b6aa444912d55c92c6dcbd99 SHA-256: 63de1cb4ff369f40a8a0975e5e006093dcfad42d06e69005d09b3acab3d06733
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm hosted on compromised CMS upload storage, with numerous embedded URLs pointing to external resources. The primary attack pattern involves luring users to click on these links, which could lead to phishing or the download of further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/c52092c65adab43ca2fe1935e5baf715/gelomer.pdf
    • https://alkathirilaw.com/userfiles/files/rojuzu.pdf
    • http://campfirewtx.org/userfiles/file/80462036820.pdf
    • http://sieuthicayxanh.vn/webroot/img/files/49496326893.pdf
    • http://gesundimjob.at/images/content/files/lupewuwiboguva.pdf
    • http://nakloboucku.cz/uploaded/file/67419851063.pdf
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/11672fda7919db190bf6634fe65aaabc/nojapebudupabidirotebajor.pdf
    • http://hanilkwanla.com/uploads/files/tukerutopaju.pdf
    • http://sameiroeventos.pt/ficheiros/daton.pdf
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/7412ad163920b17597af2eda0e3a0160/84620020277.pdf
    • https://actaviaserica.org/board/file/files/junerog.pdf
    • http://hak-al.com/resimler/files/14523619549.pdf
    • https://limblength-sldf.com/userfiles/file/dipaputuvuzuvelil.pdf
    • http://www.lukoilmarine.com/ckfinder/userfiles/files/sorilufube.pdf
    • https://mobilpetrol.olajpark.hu/files/files/gufimuvonipa.pdf
    • http://wxhsbl.com/ckfinder/userfiles/files/20210905_161942.pdf
    • http://www.vljainandco.com/userfiles/files/filerapapawu.pdf
    • http://travelshops.pl/userfiles/file/nobemegosafewesef.pdf
    • http://candemdientu.com/Images_upload/files/fepakekazizudiwobife.pdf
    • http://siltherm.com/ckfinder/userfiles/files/wesekuzuzi.pdf
    • http://kommunikator.nu/demo/userfiles/file///58803105658.pdf
    • https://vietucmould.com/img-vietuc/files/58159557775.pdf
    • http://35ct1.com/images/ckImageFiles/files/93715345400.pdf
    • https://estduquebec.com/scripts/php/xenocode/lib/ckfinder/userfiles/files/40470450531.pdf
    • http://xn----8sbfhu6ab4bqv.xn--p1ai/userfiles/file/lerasojaxa.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=mod+dr+driving+apk
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e4fc.bin
d9809149ac4213e1a549d4254707e5a0be75585cff5f7434c7139f6fd565f6da
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4FC 10272 bytes
font_01_sfnt_off0000fbf2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBF2 16792 bytes
font_02_sfnt_off00011404.bin
676472999b055a7cc053e1e4fd9b9d3ab3e6066dd0ddaad25d9a69eab3fb0b8f
pdf-font-stream PDF embedded font (sfnt) at offset 0x11404 18904 bytes