Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9889aa90789e9a9…

MALICIOUS

PDF

79.9 KB Created: 2021-06-17 19:33:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 80d1709c2f5571e6b5d7063165d4faa6 SHA-1: 296dbee9750fa2f9607fb8bd65c5a479460c0665 SHA-256: d9889aa90789e9a90d8335ac2469946121c9759c1e91a33fe7145199f54e30a9
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. The PDF contains a link farm pointing to multiple URLs hosted on compromised WordPress sites, suggesting a phishing or malware distribution scheme. The presence of external URIs and link farms on potentially compromised infrastructure are key indicators of this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/8e07cf76ce42c746e2db24998ddce22a/noxukewijefazu.pdf
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607f6fe0b221a---xituwu.pdf
    • http://1970fchs50thclassreunion.com/clients/1/19/19770213778af891f1b13fa25f964f50/File/50860514650.pdf
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16072d09082629---tifivejiniwofikavoji.pdf
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/3ca9i47n2m3vltkg4p8fg036cq/fadojipumodojewidinon.pdf
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/7a5f9760949cd80c04a08fa449a2b645/basibezonademepov.pdf
    • http://asokmontridental.com/userfiles/file/83071283189.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/k9p5nlpdegc451soodvmirhck5/53554348379.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/rdf01biin6mug19u7j6ihiqei6/pidegasusi.pdf
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160c718d994f96---befivunixazebe.pdf
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c7b286d93e---60004773132.pdf
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9e93d4b92f---39215059838.pdf
    • http://archi1919.com/smlclub-files/file/nisata.pdf
    • http://ahkjt.com/upfile/file/rofatuwabedujuxes.pdf
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e2371c832d---siwuzatajuvimifo.pdf
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c25ca53918---kebibabepukedi.pdf
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/2qt34d5qjlf799gb7mie07e5en/84605431937.pdf
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/qanklv2vvum83gr8tbeauolo64/34667505303.pdf
    • https://mannerfeltdesignteam.se/ckfinder/userfiles/files/joruxubetotevuxeninojog.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=skam+season+1+english
    • 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
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00010dca.bin
a9400914d70c8dc18b03781f67139dae80560eca97a0ec6074ee2ca9ea625f91
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x10DCA 21044 bytes
font_00_sfnt_off0000d087.bin
20f60447d41684c0ef151ae9217a169e0bd49dc76e71c727ba7ac1b970f68489
pdf-font-stream PDF embedded font (sfnt) at offset 0xD087 5224 bytes
font_01_sfnt_off0000e231.bin
99c055eb2a632bfead53d4eb1ff27ff625a0af5cda6952824d06e6d04e495058
pdf-font-stream PDF embedded font (sfnt) at offset 0xE231 13500 bytes