Malicious PDF — malware analysis report

Static analysis result for SHA-256 624e07c8581d530a…

MALICIOUS

PDF

89.5 KB Created: 2021-09-17 06:11:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 31c38deb7a1bded43ea206ef91ea4fc3 SHA-1: c6ce5e1fdf53b4f8e517f51780607d3e5cdf2d32 SHA-256: 624e07c8581d530a91cd04873fc6681ccf6187b981008ef01e91befae2c41e2f
126 Risk Score

Malware Insights

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

The sample was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a high likelihood of this file being used for SEO manipulation or as a distribution point for other malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://istanajp2.com/contents/files/35632999205.pdf In PDF document text
    • http://adec-interiors.net/Uploads/file/54165170372.pdfIn PDF document text
    • http://congluc.com/upload/files/19501227074.pdfIn PDF document text
    • http://hotelrefah4ter.ir/basefile/hotelrefah4terir/files/656008070.pdfIn PDF document text
    • https://hung168.tw/UserFiles/files/bujezoziniromujefeja.pdfIn PDF document text
    • http://fotosvatba.net/userfiles/file/67372750676.pdfIn PDF document text
    • https://tvsporedi.si/vsebina/51139509885.pdfIn PDF document text
    • https://xanbiente.de/userfiles/file/tivekipunisojagekuba.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613e6bc729a68---pudaletezuwiv.pdfIn PDF document text
    • http://restauraceeverest.cz/userfiles/file/8185195675.pdfIn PDF document text
    • https://ichapps.com/ichapps/ckeditor-ckfinder-integration/uploads/files/33443278478.pdfIn PDF document text
    • http://pujcovnanaradi-tvarozna.cz/userfiles/files/sofuzibutum.pdfIn PDF document text
    • http://slavutich-media.ru/userfiles/file/zajemunoximaxibura.pdfIn PDF document text
    • http://e68momo.com/shopadmin/upload/files/40901350238.pdfIn PDF document text
    • https://deitratech.com/userfiles/file/43804621159.pdfIn PDF document text
    • https://copperscraphandlers.com/ckfinder/userfiles/files/dosepebijurigoxusif.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613ce3ac83e49---79419244680.pdfIn PDF document text
    • https://ethnicminorities.heephong.org/ethnicminorities/cmsadmin/ckfinder/files/53783119949.pdfIn PDF document text
    • http://nawooelcs.com/upload/userfiles/2021/09/files/210914150037.pdfIn PDF document text
    • https://mackbeks.com/files/file/banuwajepamipitilepin.pdfIn PDF document text
    • https://domilot.com/uploader/files/71616836661.pdfIn PDF document text
    • http://filipdegreef.be/uploads/files/votiwifegefeweriwedo.pdfIn PDF document text
    • http://kovove-ploty-brany-zabradli.cz/UserFiles/File/71932903724.pdfIn PDF document text
    • https://dianthusindustrial.com/resimler/files/wofimifusobowuroxovim.pdfIn PDF document text
    • http://amindoost.ir/images/upload/files/28890156264.pdfIn PDF document text
    • http://businessvaluationapp.com/fck_files/file/junexanugibutupatera.pdfIn PDF document text
    • http://tfe-design.dk/userfiles/file/42381626766.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=crossed+ally+condie+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_off0000f853.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF853 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011065.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11065 18344 bytes
SHA-256: df2c2f44a5f039bf0aa199c9519182602a3d2bbae6b55e3c22cc2f75a06591c3
font_02_sfnt_off00013ff5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13FF5 10660 bytes
SHA-256: 9f6257b582f6c9b1c98e640b056ed815805522f9f2542bd0c25b8274a8dcbb5c