Malicious PDF — malware analysis report

Static analysis result for SHA-256 54cb7b7331ca0af2…

MALICIOUS

PDF

81.3 KB Created: 2021-08-18 05:50:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-18
MD5: b1af31f9330c21b99abf80789469a415 SHA-1: 43d7e824f2033c6721bde76307276ea7d36a085c SHA-256: 54cb7b7331ca0af2ffae28d8b735780df23d5f9530228d7b1d768ceec3a47f10
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites, suggesting a phishing or malware distribution scheme. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the overall structure and URL destinations strongly indicate a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae8b687d3f9---52835545635.pdf In PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077debf157e5---xitemotanox.pdfIn PDF document text
    • http://peggylittlelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/82928622471.pdfIn PDF document text
    • http://bonfiremadigan.com/uploads/fckeditor/file/vakusoluximoxuxutututuju.pdfIn PDF document text
    • http://master-br.ru/img/file/sadamiwonomokutotutaxixap.pdfIn PDF document text
    • http://alibabashipping.com/userfiles/file/gepap.pdfIn PDF document text
    • http://solentpodiatry.com/jackvl940/web/content/images_uploaded/file/mevepatolazejirudarof.pdfIn PDF document text
    • http://tdjl.com/uploadfile/file///2021080916500641.pdfIn PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/na34om6hk9inivk100iok1bnk6/jitetojomizakafo.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/69660231125.pdfIn PDF document text
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/6ed65f1c50b0ee418f680adc0f339ae7/fefegimunugewodurage.pdfIn PDF document text
    • http://sbnjl.com/userfiles/files/funiminexofomoditaz.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/1e4d6e0893154eec69aa8e1d2f022e42/renefo.pdfIn PDF document text
    • http://xn----8sbaqfskngn1qi.xn--p1ai/userfiles/file/lolufadopesafujozezibaw.pdfIn PDF document text
    • http://tuvanluatdanang.com/upload/ck/files/wusuje.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608587e3ed3ab---20613192125.pdfIn PDF document text
    • https://akrmedia.no/ckfinder/userfiles/files/bajukekagimiko.pdfIn PDF document text
    • https://christianklein.eu/Quansis/ckfinder/userfiles/files/xogudenabeziluma.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/096e8112aa6ada79141d4cf68412d40a/26182833132.pdfIn PDF document text
    • https://ntct.dz/ckfinder/userfiles/files/1900705976.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609835cd79a4b---nawezudogukikukose.pdfIn PDF document text
    • http://promador.pl/userfiles/file/tapiwikiziwedax.pdfIn PDF document text
    • http://pomodorolennep.de/gfx/userfiles/files/vakedipisomiwiru.pdfIn PDF document text
    • http://travisreunion.com/clients/1/1d/1d9c560ef9ee6310b862f4c9d288d7bd/File/19525164389.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/7178f7e350286c6360d07cd5444e90ff/rimowizalapode.pdfIn PDF document text
    • https://www.proctoloji.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607433eff3ee7---60224946697.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=vivaldi+four+seasons+easy+piano+sheet+musicPDF 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_off0000da06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA06 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f218.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF218 16828 bytes
SHA-256: b7e0b286cc981d2cbfaf3c0a7fc5e2df854b0aaf883d64b81f90cc8df4fb97fc
font_02_sfnt_off00011ddc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DDC 11132 bytes
SHA-256: 17c4f221aa22caf661133a759da38ca7a5ab36906c9b6357433d1be16923f8e8