Malicious PDF — malware analysis report

Static analysis result for SHA-256 688721cc73ed06e2…

MALICIOUS

PDF

98.6 KB Created: 2021-09-17 07:55:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: aa6e3bbf376e0517b3de84af6c37c5e4 SHA-1: bd6bbf0047f2ce97243c3487615feffa942caad9 SHA-256: 688721cc73ed06e2af543497c34855f17a61aa26d85dc7fbdf1416b9034b71ed
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically identified as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads or are part of a link farm on disposable hosting. The document body is heavily obfuscated, preventing analysis of its direct content, but the heuristics and URLs strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://archism.ru/uplcv?utm_term=react+design+components PDF link annotation
    • https://millvalley.com/wysiwygfiles/file/85465495139.pdfIn PDF document text
    • http://baldonimarcostudio.eu/userfiles/files/jamufawapikusek.pdfIn PDF document text
    • http://anquocrealty.com/uploads/image/files/voduretemajesejozosu.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143fc3658099---14557401091.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/517jgnk163q5mmd8qa62a2867e/jazaxawi.pdfIn PDF document text
    • https://giridhareye.org/ckfinder/userfiles/files/zufigozevizifutifole.pdfIn PDF document text
    • https://detector-billetes.com/Imagenes/file/12273587810.pdfIn PDF document text
    • https://twr1115.net/files/fckeditor/file/79120571236.pdfIn PDF document text
    • http://erodiertechnik-wenzel.de/userfiles/file/zabodozi.pdfIn PDF document text
    • http://parilka.by/var/upload/file/27346233940.pdfIn PDF document text
    • http://eaupureinternational.com/userfiles/file/29931698496.pdfIn PDF document text
    • http://kondicionery-ivanteevka.ru/upload_picture/file/nuxurixixepiganu.pdfIn PDF document text
    • http://popnmusic.fr/userfiles/file/26045960408.pdfIn PDF document text
    • http://hidropro.hu/upload/79937000493.pdfIn PDF document text
    • http://tt-ural.su/admin/ckfinder/userfiles/files/levufodaxisa.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/fah4nvfe6tht5sj0fo9rqujan6/43889662073.pdfIn PDF document text
    • http://irinaburmistrova.ru/files/serezuvatarifuwu.pdfIn PDF document text
    • http://i-harmonics.com/upload/files/mamatado.pdfIn PDF document text
    • http://www.mamafoundation.cz/ckfinder/userfiles/files/zijafiwokatetepa.pdfIn PDF document text
    • http://wimborst-ceramics.nl/ckeditor/ckfinder/userfiles/files/84696785901.pdfIn PDF document text
    • http://geyikkimya.com/userfiles/upload/file/riluleripotawejesanul.pdfIn PDF document text
    • https://nusbetaja2.com/contents/files/vubudevit.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/xapos.pdfIn PDF document text
    • 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_off00011d6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D6A 18148 bytes
SHA-256: ef372d2663e9f36aa169a06322573a09b1644bda73c7486f6c1324e7c93bbaf4
font_01_sfnt_off00014c28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14C28 10756 bytes
SHA-256: 2dc7157d611124dea06856c13d81f3c180474b52576630e6b47f0ba3b7ab6ac8
font_02_sfnt_off000164ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x164AB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1