Malicious PDF — malware analysis report

Static analysis result for SHA-256 4853f6f3f27ea459…

MALICIOUS

PDF

83.0 KB Created: 2021-09-07 12:10:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e5b4b315b4e0cdd433388e1200c3bf69 SHA-1: 702c9b5b5a16846d14fbc9dfeaa5a95467231a3e SHA-256: 4853f6f3f27ea45915f127548c2a791c2497cb7bc839456c42f3f16006fa4694
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised CMS upload directories, suggesting an attempt to lure users to malicious sites. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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 http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1607274489125d---68179919322.pdf In PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606f0b0015011---46126912044.pdfIn PDF document text
    • http://synagoge-stommeln.de/ckfinder/userfiles/files/kapenoxokob.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/160c89583328c3---zaxifusobazolijutu.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/1cd29a4c221efd9a050e8e1c2422a25c/74434156880.pdfIn PDF document text
    • http://www.supair-lux.hu/ckfinder/userfiles/files/nulujepesomanuxevati.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d83ee46e293---zewojawerir.pdfIn PDF document text
    • http://nt-module.ru/ckfinder/userfiles/files/dodosomakobinevogekimaz.pdfIn PDF document text
    • http://ambvetsanprospero.eu/userfiles/files/sakeduwipikom.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092b77352fbb---92960009860.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b4d0895040a---kabezezasetigoxune.pdfIn PDF document text
    • http://ty6600.com/userfiles/file/dumetobobibolapajaweti.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160de1955ac934---88212752953.pdfIn PDF document text
    • http://maskaevlawyer.ru/userfiles/file/76820333232.pdfIn PDF document text
    • http://xn--80aaaghhaztbcd1agjgbccsgfftf.xn--p1ai/pict/file/nuguwatonibuwakisarusele.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070c6e339749---41410708498.pdfIn PDF document text
    • http://morpheus-architects.com/file_media/file_image/file/tapifofoperixokirozow.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160ee5e0e6d36c---98616295255.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/160842d43985c4---45411966631.pdfIn PDF document text
    • http://robvancampen.nl/userfiles/file/tavixoluguribile.pdfIn PDF document text
    • http://ylpcl.com/ckfinder/userfiles/files/rafimubazulez.pdfIn PDF document text
    • http://giovanniseneca.eu/userfiles/files/jazukut.pdfIn PDF document text
    • http://thesetnews.com/images/fckeditor/file/rezukotaxofuli.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/sikifuvuka.pdfIn PDF document text
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/c83eb32e233d14c95d9f7ce36bbe9711/bunavasemukudo.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2e71cb448---90454957781.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=sharepoint+basic+interview+questions+and+answers+pdfPDF 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_off0000dd2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD2D 11284 bytes
SHA-256: 41087439e2e22c59a7da29b22819a2d85428a0135dd95fe05b269a7e78174ec8
font_01_sfnt_off0000f73f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF73F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F51 18128 bytes
SHA-256: 4634b662cfb9febb8d1ba5fb40c6924be875156fbded17d301a94b47a8b84967