Malicious PDF — malware analysis report

Static analysis result for SHA-256 35ef99e2a75028fe…

MALICIOUS

PDF

72.9 KB Created: 2021-09-03 19:48:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ebaf953d7ccf47563df8ed58dff2c748 SHA-1: 770a74b44083c2590f64dd678cf0ad591e921a71 SHA-256: 35ef99e2a75028fed77dfec6ce76f9b072122160807e71cc4c6d0ffd04c55183
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, pointing to multiple compromised WordPress sites and disposable hosting domains. The embedded URLs suggest an attempt to redirect users to potentially harmful content, consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfaf2de24b2---95478436276.pdf In PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/u8blbg67uk33o6ofiq1e8p0fuk/36658264183.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ba1b096e0fd---24901056020.pdfIn PDF document text
    • http://commsoft.nu/demo/ktb/wsmbilder/files/miteravig.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/lmc2u5bfkmig49v3rcclenm2qj/nidakene.pdfIn PDF document text
    • http://adamslakeband.org/userfiles/file/xirafunesodijusab.pdfIn PDF document text
    • http://tehnicgaz.eu/files/file/31406842775.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/f8f0u5hcv64b0so2osbg3lljr3/raxusixixu.pdfIn PDF document text
    • https://tekartltd.com/upload/files/wunoromenejika.pdfIn PDF document text
    • http://polyalpan.hu/_user/file/guraruparalumer.pdfIn PDF document text
    • http://share-world.tw/userfiles/file/lumagemunelinupa.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ab973346bbce330d2adea978c18e7141/9645751015.pdfIn PDF document text
    • http://bluekeydigital.com/images/pic/file/88914098338.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ee2c8bc3fa---58418703198.pdfIn PDF document text
    • http://www.multigacos.com/admin/uploaded/fck/file/gawuta.pdfIn PDF document text
    • https://brahmagnanam.org/fck_uploads/file/65748897575.pdfIn PDF document text
    • http://evolution-dev.com/file_media/file_image/file/27320706388.pdfIn PDF document text
    • http://jadeite.ru/images/file/sopemoxebokofapisozog.pdfIn PDF document text
    • http://canxetaidientu.com/images/file/43884600231.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607add53e6759---86542429946.pdfIn PDF document text
    • http://abpaluso.com/upload/file/favixukowam.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a53af574975---wipinatazo.pdfIn PDF document text
    • http://rosg.net/sa_upload/userfiles/file/20210822122241.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d32122258b5---doderepolirexige.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=punctuation+paragraph+worksheets+for+grade+2PDF 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_off0000bac2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBAC2 16024 bytes
SHA-256: 8a5d643b1e178f52785d51bc72b8e92153e961b8f8db6afb599fc186a440785f
font_01_sfnt_off0000e3bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3BF 11252 bytes
SHA-256: 1fe717fbf5b56d53d8b8147269fedfb18a95562a4f02e5ef9d2011350a450ba2
font_02_sfnt_off0000fe17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE17 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1