Malicious PDF — malware analysis report

Static analysis result for SHA-256 4570d5ce18f4c1bc…

MALICIOUS

PDF

84.8 KB Created: 2021-09-17 08:45:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 8c9d3253cb4b45693955aff42608262f SHA-1: 5763bbccf09fd8d8aad763575ad7f96b1d52808b SHA-256: 4570d5ce18f4c1bc9b24417378f4fdb53c55d3dd880dcd86865756671be3d6eb
126 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 as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external PDF files hosted on various domains. The presence of numerous embedded URLs, many with 'utm_term' parameters, suggests a coordinated effort to distribute malicious content or phish for information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://crewmak.ru/uplcv?utm_term=android+app+nulled PDF link annotation
    • http://fatename.com/uploads/files/202109041631187112.pdfIn PDF document text
    • http://hit-air.pro/ckfinder/userfiles/files/retegulajibujanavosufa.pdfIn PDF document text
    • http://avvocatogiuliani.it/userfiles/files/vapupevaleguvokaj.pdfIn PDF document text
    • http://brickchamber.com/ckfinder/userfiles/files/91174487464.pdfIn PDF document text
    • http://tacchigroup.com/public/thread/risorse/file/fogekupevamosesarelimumix.pdfIn PDF document text
    • https://biogenetixpharma.com/ci/userfiles/files/28471385669.pdfIn PDF document text
    • https://kisikana.hr/userfiles/file/80167399588.pdfIn PDF document text
    • http://turnwealthy.com/ckfinder/userfiles/files/47450734613.pdfIn PDF document text
    • http://bsinteriordesigner.com/userfiles/files/topigu.pdfIn PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136e1df597c9---24759643107.pdfIn PDF document text
    • http://permagnet.com/upload_files/file/2109110403113857979m8i21.pdfIn PDF document text
    • http://swaving-stalinrichting.nl/ckfinder/userfiles/files/bifegiwaxobifaweber.pdfIn PDF document text
    • http://sochi-riba.ru/ckfinder/userfiles/files/77835555047.pdfIn PDF document text
    • http://ldksolar-officialliquidation.com/userfiles/files/63810658647.pdfIn PDF document text
    • https://boucherienabli.com/uploads/FCK_files/file/funesejixewoz.pdfIn PDF document text
    • http://technestudio.eu/userfiles/files/22762497970.pdfIn PDF document text
    • https://kaktutzhit.by/uploads/files/sofidimawedexoxovad.pdfIn PDF document text
    • http://bugaboo-buffalo.eu/UserFiles/File/90305490094.pdfIn PDF document text
    • https://nslogisticservice.com/userfiles/files/20947200059.pdfIn PDF document text
    • http://codienlanhtrangia.com/Images_upload/files/40120676420.pdfIn PDF document text
    • https://kfk-dekoration.dk/images/uploadedimages/file/24200426448.pdfIn PDF document text
    • http://yuanhebiotech.com/upload/files/kemubokeroxijenewu.pdfIn PDF document text
    • http://vina2002.com/uploads/files/75786475459.pdfIn PDF document text
    • https://akvaguru.hu/user/file/bisimisukazibujotenezego.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fe427cd1d5---60323995001.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_off0000e83a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE83A 10200 bytes
SHA-256: 74ced64eed6d3cdc33ec2adb86812d3dd5f141930f39ca9b17bbe3d87c19e224
font_01_sfnt_off0000ff15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF15 18056 bytes
SHA-256: bef8f740889bd908563db78d6427dca6846aec32a0a236e92fee91e0cd83b39d
font_02_sfnt_off00012e01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E01 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1