Malicious PDF — malware analysis report

Static analysis result for SHA-256 43f2a9c0f9d4f0a8…

MALICIOUS

PDF

75.7 KB Created: 2021-09-13 16:25:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 53019842dce9c4e9ff28e532dcad4c37 SHA-1: 2a4f4130620ea6a531617563e1037ee67cf9d934 SHA-256: 43f2a9c0f9d4f0a8f393f8bb16830216586c97777b966d677abfe3ef46ab69c7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and a significant number of external URIs, many of which point to compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. The embedded JavaScript is a common technique for executing malicious code within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 7

  • 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.
  • 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.
  • 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://synerhu.ru/uplcv?utm_term=sweet+snap+download+apk
    • http://wernitznigg.at/files/fotoluj.pdf
    • http://philboyd.com/sujaxavumajanepedumazetid.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/52f582b6d9616cf54912efe274aa7e6c/witivuzoku.pdf
    • http://ibrahimalsada.com/pics/file/40532248323.pdf
    • https://aluminiosarla.com/userfiles_arla/files/nadikosuzuwetipalifi.pdf
    • http://peach2560.xyz/js/ckfinder/userfiles/files/65302984892.pdf
    • https://pasarant0g3l-turbo-h1t.com/contents/files/nekoluzelilosuniporis.pdf
    • https://lesura.net/userfiles/file/rotekuxe.pdf
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/161391caca2eb2---loboxezavufijomi.pdf
    • http://numismatika-nbkpdy.cz/userfiles/file/36998939837.pdf
    • http://technoprofile.ru/userfiles/file/97724638863.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/161380442921aa---lotimudezaludorivefuviwi.pdf
    • https://masihpt1.com/contents/files/31731574997.pdf
    • http://xycrusher.com/d/files/76641068535.pdf
    • http://xn--80aejmo0alc.xn--p1ai/ckfinder/userfiles/files/gelidolujusogate.pdf
    • https://kitchensofdiablo.com/upload/file/joganexil.pdf
    • https://kamarkosong.com/contents/files/239773785.pdf
    • https://livnica-metalurg.com/images/pages/file/63121144419.pdf
    • http://praguynakorn.com/praguynakorn/picture/datapro/files/84897356614.pdf
    • http://edu-soft.ru/site/htmlimages/file/bazefutusogikijosupomudil.pdf
    • https://ambalatender.com/upload/files/23483097585.pdf
    • 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_off0000c42b.bin
f079cfb6de05f69257745eb7b1cc00bb410494e0900fed5feba092d7964934b3
pdf-font-stream PDF embedded font (sfnt) at offset 0xC42B 17856 bytes
font_01_sfnt_off0000f18f.bin
ab06ecc97cede954fc760f2a1c1d1eb8827ba4a3d1b73e6687514e1d5d1945fa
pdf-font-stream PDF embedded font (sfnt) at offset 0xF18F 10448 bytes
font_02_sfnt_off00010976.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10976 16792 bytes