Malicious PDF — malware analysis report

Static analysis result for SHA-256 f843aff66ade47b9…

MALICIOUS

PDF

126.7 KB Created: 2021-06-26 13:21:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d145fb5f166de625792ffcc13d49a387 SHA-1: 668104d41849afa6ff49f0ac9691002cfdbd0fb0 SHA-256: f843aff66ade47b9d2a0bca6c8eb556cef9951fe35072b0124d68b81f07a61ad
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting a phishing or redirection scheme. No scripts were extracted, but the PDF structure itself is used to host numerous links, likely for a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://xn--fct8ml6mwue.tw/uploads/files/53229577996.pdf
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b331cd8d570---97301841479.pdf
    • http://ippon.lv/uploads/File/47643982403.pdf
    • http://manavpublicschool.org/manav/userfiles/file/bewerugoxelo.pdf
    • http://www.radiooro.com.mx/media/images/uploads/files/65803411428.pdf
    • http://www.sealjet.mn/pictures/files/65894740341.pdf
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d97baec13a---gajemarejibuz.pdf
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/ac62cc1885864638b70f6ca28bbcf213/vaxewatiwexotijowesamu.pdf
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/f9d64095e51e1d292afffc831981c9e3/numugezesowedabi.pdf
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070d273b4b34---mobemenenudeg.pdf
    • http://aite-materials.com/upfiles/file/nawekegogamosirodexapin.pdf
    • https://acronimocostanzo.com/userfiles/file/61198208174.pdf
    • http://phayaotechno.com/UserFiles/File/nodezikaposasaj.pdf
    • http://animalscipublisher.com/files/upfiles/file/nizapuwexofimeki.pdf
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160717b0d3e689---fitufukugo.pdf
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/16089e32e6ccbd---28809810291.pdf
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16086fccc94c72---monemudevejonavud.pdf
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/3dd3caff9ab54db48c55e74011c153c3/fumulosowekelufegosame.pdf
    • http://from.ua/upload/articles/2021/06/17/files/87537483174.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c4508dcf781---58571840369.pdf
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f8ad15c66e---zoxubel.pdf
    • http://avtrak.ru/ckfinder/userfiles/files/wefobadokewebabaw.pdf
    • http://apsons.eu/files/file/vevaxajaxififewotegevib.pdf
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/ct5p66k46e3gq1ufmlb6dpjkfp/81879780250.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=technology+diffusion+theory
    • 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_off00018ab5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x18AB5 16792 bytes
font_01_sfnt_off0001a2c7.bin
a9409c029ecec15371e7577a35e573689b99fc78e6738b77d810cdb13c094ec6
pdf-font-stream PDF embedded font (sfnt) at offset 0x1A2C7 18900 bytes
font_02_sfnt_off0001d47f.bin
23f4cb001817b6b8dd3c0854478594d67c204bc0290225850415bba6806547c7
pdf-font-stream PDF embedded font (sfnt) at offset 0x1D47F 10772 bytes