Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdd77a74f6e2a366…

MALICIOUS

PDF

80.2 KB Created: 2021-09-19 16:22:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 93308d6f6b7cf85e964f0755b2c07e57 SHA-1: 8ceb00ccd2f22a3dff2d94c94c847a6eea3ca936 SHA-256: cdd77a74f6e2a366c9cd562bb4ce2302e00a4daee5cebca1150f53666abb7551
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://krisoc.ru/uplcv?utm_term=statistical+methods+for+research+workers+pdf PDF link annotation
    • http://jingyilin.org/uploads/file/71545688747.pdfIn PDF document text
    • https://videoeffect.ir/data/file/39968000368.pdfIn PDF document text
    • http://dga.gr/ILC/img/file/15669095939.pdfIn PDF document text
    • http://elitacasa.it/images/file/pukavifot.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613f557a9206b---delugatikubitimafanapa.pdfIn PDF document text
    • http://thuocamakong.net/userfiles/image/file/mojup.pdfIn PDF document text
    • http://ratchadatitan.com/UserFiles/File/91270924050.pdfIn PDF document text
    • http://canadianrockies.ca/files/file/desov.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cee436dc85---93713994654.pdfIn PDF document text
    • https://www.autopsrus.com/ckfinder/userfiles/files/riximesulasabofotixavem.pdfIn PDF document text
    • http://clinicaveterinariagoitese.it/userfiles/files/84663757407.pdfIn PDF document text
    • https://muachungbaohiem.com/uploads/userfiles/file/54911204243.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/161434862e6558---31651218067.pdfIn PDF document text
    • http://beijingteye.com/upload/files/fepotodefelaxusape.pdfIn PDF document text
    • http://spain-ex.com/images/blog/file/77024065150.pdfIn PDF document text
    • http://sobateracota.ro/mm/file/45373405232.pdfIn PDF document text
    • http://sky1981.com/asset/uploads/files/54587618642.pdfIn PDF document text
    • http://pune-india.info/userfiles/file/12501740450.pdfIn PDF document text
    • http://box8websites.com/ckfinder/userfiles/files/72531347048.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d390fdfa3fd6d8a44b307530e045507d/surutisa.pdfIn PDF document text
    • https://orsam.org.tr/paketler/ckfinder/dosyalar/files/79429784900.pdfIn PDF document text
    • http://archidaldegan.eu/userfiles/files/97163062688.pdfIn PDF document text
    • https://5uempat.com/contents/files/jeteni.pdfIn PDF document text
    • http://silverspringabw.com/uploads/files/bafezejesupawiwogab.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_off0000d1f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1F0 11032 bytes
SHA-256: cbf7f4ddfa6f07a60a2285a55f8bf74521e646d0a683e93be13f982012eaf4dc
font_01_sfnt_off0000eba5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000103b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103B7 18144 bytes
SHA-256: 02a68f62e26d5255332267fe45b6013f640a3720d69bc51a959a5ed03fcfe566