Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cd79d00d6ed2c76…

MALICIOUS

PDF

77.9 KB Created: 2021-09-10 18:53:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: f4493bd936a3618a22272588050f98b6 SHA-1: a3d5bd5d724df6a832729580a2990067b788bdee SHA-256: 8cd79d00d6ed2c76886e1d2d5877812dff34ef61611434da96c7a8860dbf716e
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 5

  • 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://philabc.ru/uplcv?utm_term=kinematics+of+fluid+flow+pdf PDF link annotation
    • https://diedacorporation.net/freesiafiles/file/bufekovetizepawitebekuzo.pdfIn PDF document text
    • http://meuble-tunisie.com/userfiles/file/3485341388.pdfIn PDF document text
    • https://ra7a7p-h3ba7.com/contents/files/zanopuzabapawuliwinuj.pdfIn PDF document text
    • http://amexeuro.com/an3_Uploads/file/kejemoxowuwulujumusu.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/6cdrl39141mj07vop1hc3i2keo/12757573734.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/f7ae515602888bc5713c2a8aac54eccf/ziwujirunejefeleki.pdfIn PDF document text
    • https://organicearthfiji.com/documents/file/gajokupotumafij.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/cd39969df8e0a56fcb33e0d6aada0417/64082885585.pdfIn PDF document text
    • http://educasters.co/ckfinder/userfiles/files/kojogevoritoxuxovapa.pdfIn PDF document text
    • http://lukinserv.hu/file/79860645995.pdfIn PDF document text
    • https://ietc-oman.saktoon.com/userfiles/files/kiwiran.pdfIn PDF document text
    • https://anjingliar.com/contents/files/tujiserupuxenegowasakul.pdfIn PDF document text
    • http://exhibitionchannel.com/upload/65261234927.pdfIn PDF document text
    • https://zakarpattya-tour.com/upload/93959915459.pdfIn PDF document text
    • https://bodymart.in/ckfinder/userfiles/files/bikod.pdfIn PDF document text
    • http://emons-verlag.net/testarea/cwsCMSlight/media/files/38981983573.pdfIn PDF document text
    • http://www.naraihillgolf.com/admin/userfiles/file/96605803604.pdfIn PDF document text
    • http://yaqeen-eg.com/userfiles/file/21595371504.pdfIn PDF document text
    • http://vita24h.com/uploads/userfiles/file/xofibufinexujeripivamapux.pdfIn PDF document text
    • http://launensia.cz/ckfinder/userfiles/files/5852981052.pdfIn PDF document text
    • https://manenshop.com/upload/files/lemipurofexolowe.pdfIn PDF document text
    • https://korovin.org/site/img_ufiles/17673530800.pdfIn PDF document text
    • https://biogenetixpharma.com/ci/userfiles/files/7052291151.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612feb788b266---642151018.pdfIn PDF document text
    • http://studiomanzetti.it/userfiles/files/wodigig.pdfIn PDF document text
    • https://fcksa.com/ckfinder/userfiles/files/rujatawewuxibamaneli.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_off0000cf7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF7C 10860 bytes
SHA-256: b16a9bd7e2442effa6779ff2f06c2261bd4d9972e98f3844f9a0c13df0cde345
font_01_sfnt_off0000e89d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE89D 16132 bytes
SHA-256: 758f3a4a5fb4aa8a910857b28ac5f640d1413fd443be94131019d6fbc73af55e
font_02_sfnt_off000111aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1