Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1958ab5fff51569…

MALICIOUS

PDF

78.1 KB Created: 2021-09-12 12:08:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c8552bebb66363f2d35dc2b6c90c71eb SHA-1: b31921bde53006ebc835b8c7127ebb227df68cdb SHA-256: b1958ab5fff51569e3ff75d254f0ec1f2995930b5e2b55b349f79deaa38a7aa4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to potentially malicious domains. The presence of PDF_SEO_DISPOSABLE_LINK_FARM suggests an attempt to obscure the true malicious intent through a large number of low-reputation links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://lubrifianti-auto.ro/files/file/57210952857.pdf In PDF document text
    • http://eska-lift.ru/userfiles/file/guwojinug.pdfIn PDF document text
    • http://kencert.vn/uploads/image/files/21725712949.pdfIn PDF document text
    • http://mirutte.com/newsfiles/files/vopoluporosuzexaw.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135317b7ee3e---vexidomun.pdfIn PDF document text
    • https://youxsoft.com/uploads/files/50937672397.pdfIn PDF document text
    • http://njbeihang.com/uploadfile/file///2021090710460560.pdfIn PDF document text
    • https://www.rougeindigo.com/ckfinder/userfiles/files/sexaba.pdfIn PDF document text
    • http://fairfresh.net/assets/admin/ckeditorimage/files/zasemetujigutudalotine.pdfIn PDF document text
    • https://rhuyscampingcar.fr/images/files/rulovibivoxaluvisifo.pdfIn PDF document text
    • http://carrasvilla.es/uploads/files/bikagijonawuliwibi.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613859905a63a---xudapofejebiminazefeja.pdfIn PDF document text
    • http://craft-personal.de/userfiles/file/96097546872.pdfIn PDF document text
    • https://numen-wow.com/userfiles/cloud/files/12107659800.pdfIn PDF document text
    • http://highlevel.pl/userfiles/file/wunoninakagezazu.pdfIn PDF document text
    • http://jplus-ag.com/upload/files/BodyFile__6135AB2B1F356.pdfIn PDF document text
    • https://promobryansk.ru/userfiles/files/64089026429.pdfIn PDF document text
    • http://ruihuitax.com/files/file/89092535564.pdfIn PDF document text
    • https://gcr.goldcrownresort.com/magazine_files/files/64549751012.pdfIn PDF document text
    • http://sitoad.com/bbqjoekey/files/202109050105231852.pdfIn PDF document text
    • http://arcomproltd.com/userfiles/file/rojeselatagadibodap.pdfIn PDF document text
    • http://www.plan.msu.ac.th/ckfinder/userfiles/files/ditotepijafuliriwa.pdfIn PDF document text
    • https://oilbasaro.com/web/images/ckfinder/files/20210910122118.pdfIn PDF document text
    • http://commissioncollectionlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zaxedopumedokubulevatafe.pdfIn PDF document text
    • http://suachuadienlanhhoaphat.com/hinhanh_fckeditor/file/79431324852.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=android+top+navigation+barPDF 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_off0000d208.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD208 10408 bytes
SHA-256: 44ba96ca4e934125e13007d6cd068d6060430923ee21647434839129ff8b3837
font_01_sfnt_off0000e941.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE941 16144 bytes
SHA-256: 4ba8d562a871ae9fb426895f54a232b238233856a83e9a405823a88a0bdac7e9
font_02_sfnt_off000112e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112E3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1