Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1aa6eff9f032235…

MALICIOUS

PDF

69.0 KB Created: 2021-10-01 09:10:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 106b5546275038cd51f4fe920226a812 SHA-1: 1ad292fe398568b0c6232ee259b9fef550b633c8 SHA-256: c1aa6eff9f0322350c27cad2f6eb965c9c746aaaa76c12bb77fa876339956fb0
156 Risk Score

Malware Insights

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

This PDF was flagged by a machine learning classifier and ClamAV as malicious. It contains a link farm with numerous URLs, many hosted on potentially disposable or compromised domains, suggesting an attempt to direct users to malicious content. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://ylwlgwadmin.ylwl.cn/upload/files/47022340843.pdf In PDF document text
    • http://gzcaifeilai.com/ckfinder/userfiles/files/202109100314575561.pdfIn PDF document text
    • https://jasmijnbloemengroen.nl/userfiles/file/80478024663.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ab19fcc6e0---beledalulalafopa.pdfIn PDF document text
    • http://indel.sk/userfiles/file/tubemosonupogiduwadadug.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16142795711c31---gujifufulugoxuja.pdfIn PDF document text
    • http://thebeautyofdesign.nl/ckfinder/userfiles/files/35940656341.pdfIn PDF document text
    • https://ylwlgwadmin.ylwl.cn/upload/files/zarunebifirali.pdfIn PDF document text
    • https://muzeumkonstancina.pl/attachments/file/35853749953.pdfIn PDF document text
    • https://adasms.fr/userfiles/file/kidijotejuxane.pdfIn PDF document text
    • https://mahanakhon.pacedev.com/ckupload/files/kipawodeto.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/ru0phif81ih3kc75fetr8bb9vu/tenubenaluwepawom.pdfIn PDF document text
    • http://e3edu.vn/public/ckfinder/core/connector/php/connector.phppublic/uploadsfiles/25604924578.pdfIn PDF document text
    • https://presstone.hu/userfiles/file/40132708586.pdfIn PDF document text
    • http://tinhdauvietnam.vn/upload/files/tidaz.pdfIn PDF document text
    • https://fratellifurloni.it/file/88654305038.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/15b2nr3jubofeur5qkatv34367/33717198940.pdfIn PDF document text
    • http://dentalcenterstudio.it/userfiles/files/ziketisepulad.pdfIn PDF document text
    • http://kkagro.com/media/images/upload/file/javozugofifapafefov.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/15364118148.pdfIn PDF document text
    • https://thefertilizerproductionline.com/d/files/10182884730.pdfIn PDF document text
    • http://happy-land.hu/editor_up/63264285604.pdfIn PDF document text
    • http://locum-system.pl/userfiles/file/64439653578.pdfIn PDF document text
    • http://parkingparts.com/Upfiles/file/mapigipi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=pdf+jurassic+parkPDF 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_off0000af48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF48 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c75a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC75A 15676 bytes
SHA-256: 5eab126fdde6e381a429b991f813f1ee55709241ed95205f82aa4f2927a72940
font_02_sfnt_off0000ef2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF2A 10436 bytes
SHA-256: 535b43a46b8ea2dd980bb96693a103390554d26bda2e17c349833037493cf748