Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5ff9e85ff4658ee…

MALICIOUS

PDF

92.8 KB Created: 2021-09-21 22:28:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 824e094acd6b514b87c61a3648e2be38 SHA-1: 64492c9b825e78241d89c3cf4200f6891eccef0d SHA-256: a5ff9e85ff4658eee0f8bec753b1cedd5a90ac053b4290e1538f8a02807c68de
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many embedded URLs pointing to potentially compromised or disposable hosting sites. The presence of multiple PDF link farm rules suggests a deliberate attempt to obscure the final malicious destination, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://ingegnasrl.com/userfiles/files/molixurezajawog.pdf In PDF document text
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/932bf9097b2899fe0616efac462b986e/78683302079.pdfIn PDF document text
    • https://pisangmanis.com/contents/files/tububo.pdfIn PDF document text
    • http://polaryachts.com/res/wysiwyg/file/zovakobinedilok.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/tasoroxemepivi.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/4199c69d27bdeebab03de3e8c5026b5c/davedogipogu.pdfIn PDF document text
    • http://bndweb.nl/upload/files/76290986503.pdfIn PDF document text
    • http://ipost.mn/ckfinder/userfiles/files/gebawekewudegovenes.pdfIn PDF document text
    • http://3qlohas.com/CKEdit/upload/files/85036778910.pdfIn PDF document text
    • https://www.hasmow.com.au/application/third_party/ckfinder/userfiles/files/74294636657.pdfIn PDF document text
    • https://dotcomtravelegypt.com/userfiles/files/nejomevifuraxu.pdfIn PDF document text
    • https://agentcctv.com/userfiles/file/99751477957.pdfIn PDF document text
    • https://centaur.vri.cz/docs/files/85897985292.pdfIn PDF document text
    • https://taucaotoccatba.vn/images/news/files/gexujakorerelofogamima.pdfIn PDF document text
    • http://bigbulkbags.ahmadpackages.com/survey/userfiles/files/masitoxomumikitonulok.pdfIn PDF document text
    • http://labradory.pl/file/zerelabo.pdfIn PDF document text
    • https://qatarsecurityservices.com/public_html/userfiles/file/mexonipupafeva.pdfIn PDF document text
    • https://juhaszautovill.hu/userfiles/file/42913617083.pdfIn PDF document text
    • https://picinterior.com/ckfinder/userfiles/files/2257007328.pdfIn PDF document text
    • http://thegioimercedes.com/upload/files/xaluxekibotovoperalikal.pdfIn PDF document text
    • https://g55net.com/webpagebuilder/ckfinder/userfiles/files/18234713787.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/940632d92674f0c60540d2bf1d37fbdd/nejakeme.pdfIn PDF document text
    • https://tezerwatch.com/file/upload/files/09-16-11-36-36-56.pdfIn PDF document text
    • https://sportyou.fr/ckfinder/userfiles/files/9009516809.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=aide+pdf+to+dxf+converter+free+downloadPDF 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_off00010473.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10473 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011c8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C8A 10680 bytes
SHA-256: 9a44ec314256a44ce4080a4d7def229dcd5420a2625a9fe708a915c9302d30a6
font_02_sfnt_off00013534.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13534 18332 bytes
SHA-256: 5642ef5fe749b423f38e896f4e316b4f3bc6db2cdfac0510be78d12e54a62019