Malicious PDF — malware analysis report

Static analysis result for SHA-256 94fcb5f439df1543…

MALICIOUS

PDF

80.8 KB Created: 2021-09-12 22:34:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7a735c1fad5cbeb49707eb46d762ae7a SHA-1: 91e19e617ce805c05c6882b7c379e77e95bdc5e7 SHA-256: 94fcb5f439df154333ad900d5203b1bb929ff38f6d8527bf20dcd2913f2cc8d9
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The sample is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it's a link farm and a social engineering lure to install browser extensions or updates. The document body is heavily obfuscated, preventing a detailed analysis of its specific content, but the presence of numerous unknown URLs suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://88cpap.com/userfiles/files/sedewiboxujo.pdf In PDF document text
    • http://rafaelstore.ru/upload/files/95128298335.pdfIn PDF document text
    • http://chupanhnoithat.vn/upload/files/ponaxax.pdfIn PDF document text
    • http://starroadchina.com/userfiles/file/gimelilikimuruvelesus.pdfIn PDF document text
    • https://culturasiapamplona.com/guiarte_userfiles/files/34985189310.pdfIn PDF document text
    • https://armenia4d.com/contents/files/ziwisi.pdfIn PDF document text
    • http://thesnowmanicecream.com/ckfinder/userfiles/files/58268423451.pdfIn PDF document text
    • https://acrgroup.nl/userfiles/file/66297536796.pdfIn PDF document text
    • http://union-montage.pl/userfiles/file/lazexusibozukafanoxuru.pdfIn PDF document text
    • https://tavfelugyelet.megujuloenergiapark.hu/admin/ckfinder/userfiles/files/lubasewutofaxi.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/fb904c35d0e15c02c353e6c364a1a0bc/teropamafezaguzeb.pdfIn PDF document text
    • http://goteneplast.se/files/images/file/lexeleserobuniwalukesovo.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/lalotudura.pdfIn PDF document text
    • https://relaxbotanika.cz/ckfinder/userfiles/files/87570911382.pdfIn PDF document text
    • http://concilianavarra.com/userfiles/files/94043466444.pdfIn PDF document text
    • http://precisionsurgicalworks.com/alpha/ckfinder/userfiles/files/bupokalidizipi.pdfIn PDF document text
    • http://abwcrainhwy.com/uploads/files/tajikuwixowesuwalit.pdfIn PDF document text
    • https://taechoclub.com/FileData/ckfinder/files/20210902_223DA8F8850DC6A2.pdfIn PDF document text
    • http://feuerwehrobrigheim.de/upload/files/47234493996.pdfIn PDF document text
    • http://kahasat.cz/data/file/nataxomojezulavuxabivafox.pdfIn PDF document text
    • http://chinazzjx.com/d/files/27992945555.pdfIn PDF document text
    • https://vanphongphampmc.com/upload/files/49082213056.pdfIn PDF document text
    • http://xn----7sbab1bcaqplb0ccyi9d.xn--p1ai/files/file/83668406495.pdfIn PDF document text
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/b513d8672e866e4e89ff5371837842ab/wufikuketoxudoninosuvo.pdfIn PDF document text
    • http://thelifelesson.net/home/tappingchanges/public_html/dowalumniusa/ckfinder/userfiles/files/raraxe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=android+apps+on+windows+pcPDF 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_off0000d84e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD84E 10296 bytes
SHA-256: 197661f68ddc3976124072c921db8d27a6bf6aa4bded2b6b2e7af8d7279b73cb
font_01_sfnt_off0000efa5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFA5 17904 bytes
SHA-256: 08290df3713e7c66fc79f4861e429265fa054d3334ba11d5ab3cd51fc2bbe251
font_02_sfnt_off00011dcb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DCB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1