Malicious PDF — malware analysis report

Static analysis result for SHA-256 b99249628bdba47f…

MALICIOUS

PDF

74.6 KB Created: 2021-09-12 17:11:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1783e9519e5558a06b192eca85e4c1ca SHA-1: 95952a9327bf9e658a207aa656c1f74cdf3970cc SHA-256: b99249628bdba47fb99c6a470e990cd283a40023ae7cbbf3e8ecfd9e8b084711
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised or disposable domains, suggesting a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the PDF structure and link farm characteristics are indicative of a phishing or malware distribution attempt, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://taiwan-tsai.com/upload/files/kabezav.pdf
    • http://szyqjsj.com/UploadFile/file/20210912191959557.pdf
    • http://sfipl.in/userfiles/file/16823988645.pdf
    • http://suvenirzp.com/uploads/files/rabenabe.pdf
    • http://heathrowairporttaxi.website/userfiles/file/mipumemu.pdf
    • https://artesapanaderia.xyz/aym_image/files/86154592332.pdf
    • https://getadoc.in/ckfinder/userfiles/files/27883381976.pdf
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/63c3bddb4ac76d48af623f1a866c2988/36909157368.pdf
    • https://cartolmania.it/file/44889281305.pdf
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161339e9f297f4---bunom.pdf
    • https://naucharts.com/ckfinder/userfiles/files/fomevaxoxumuwoja.pdf
    • https://icbacademy.com/upload/files/mokibukanef.pdf
    • http://quesnelbusinessnetwork.ca/userfiles/file/12886051591.pdf
    • http://clinicaveterinariagussago.com/userfiles/files/86821294451.pdf
    • http://virtuozi.ru/sites/all/sites/virtuozi.ru/files/4980976077.pdf
    • https://ratoempat.com/contents/files/tabifoziloluzelaxax.pdf
    • http://steelbo.com/uploads/admins/u0/files/20210910192523.pdf
    • http://ptk-tent.ru/userfiles/file/39875536269.pdf
    • https://chulintemple.org/CKEdit/upload/files/23370229939.pdf
    • http://upservice.expert/admin/ckfinder/userfiles/files/7299413413.pdf
    • https://egc.ecrom.work/syo/files/11614912738.pdf
    • https://ms01bet.net/contents/files/43949621392.pdf
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613405545c0ff---40132606822.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=show+battery+percentage+apk
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bf26.bin
02220e6b82c310b562edeedbf85df7f880359c840c6329536c0030aabe1a8b59
pdf-font-stream PDF embedded font (sfnt) at offset 0xBF26 17552 bytes
font_01_sfnt_off0000ec41.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC41 16792 bytes
font_02_sfnt_off00010458.bin
29268dbb52d35a9aea2cab1e8622d59b1a9e2f000ee43a1098093a1da35f171a
pdf-font-stream PDF embedded font (sfnt) at offset 0x10458 10852 bytes