Malicious PDF — malware analysis report

Static analysis result for SHA-256 f44fa432d6b85cd8…

MALICIOUS

PDF

97.9 KB Created: 2021-07-04 17:58:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 350aabf3b1ebc2ddaf9ad14c578f6c9b SHA-1: 7156fffd56d140f47a77058340b7f90a2d78244e SHA-256: f44fa432d6b85cd80a908d71fb53f54317a6f1c2befa7017b4b76eeb05a85b15
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or delivering malicious content. Heuristics indicate the PDF acts as a link farm, pointing to multiple compromised WordPress sites and disposable domains, suggesting a phishing or malware distribution campaign. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9928

Heuristics 8

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://changrung.com/ckfinder/userfiles/files/wibejilevalomorewiwetade.pdf
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099c91e2ea09---dexojidules.pdf
    • http://nbpcpentecostalchurch.com/clients/65183/File/nuwulenoxogogevidukeve.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0e76df2f69.pdf
    • http://garage-fuji.jp/js/upload/files/lixof.pdf
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c394a0c42e2---tukopedelop.pdf
    • http://beetsom.com/PROGRAM_FCKeditor_UserFiles/file/19157169760a5dc2276255.pdf
    • https://seataclightingalaska.com/wp-content/plugins/super-forms/uploads/php/files/9746c90df8f7a75cdb624af96d7c095f/retalulawozefubekikibaj.pdf
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080371460679---kipijadimuvuzawodejozun.pdf
    • https://p87.hu/files/55552825047.pdf
    • http://silesiacapital.eu/data/file/ravulisofogotikuxet.pdf
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160d6d0be1f983---wariviv.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e9d483034f.pdf
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/dd3b01e7bde78e410deb25d74a586be5/xagifasaruxuleg.pdf
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/vhmutbotnegjacf2orahcltsv3/dosebesozuzekulagiluv.pdf
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/0d3b25bf69483337985bc4a53bd524db/wawuwamovosoledoxosamor.pdf
    • http://easternsheep.by/app/upload/file/dazebikelixubosugoroz.pdf
    • https://angkoronetour.com/userfiles/file/xexisufaxoj.pdf
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609d0a2f6f332---galupudasedivi.pdf
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/8a0173644ddf1f8ccf25870f3c0f3f51/tuvuxunopejelibemoxokig.pdf
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609359d007c32---xisebufik.pdf
    • https://ropaalmayoreo.com/images/userfiles/file/77651603934.pdf
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/d266547d2ed4ad7f50bdcd4130b65bb2/75951777498.pdf
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/1632987d922f6cd04178cc838f83e169/25237167406.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=signs+of+listeria+poisoning
    • 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_off00011a9e.bin
bee54cbb1b795a4b82f385234068b1b40cdd379eefede4e7ea133165648eb973
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A9E 18496 bytes
font_01_sfnt_off000149a2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x149A2 16792 bytes
font_02_sfnt_off000161b9.bin
f25d74b04b8fe5e00d9df5b0874301debd02ff89b8b11c6a61d57b1c612758b6
pdf-font-stream PDF embedded font (sfnt) at offset 0x161B9 10608 bytes