Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a837dd2e874a4aa…

MALICIOUS

PDF

75.8 KB Created: 2021-09-12 16:14:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 53f256e2dad622f3e440bab2f475a725 SHA-1: 2ba3124fec30b18e22028d148320258f16131a85 SHA-256: 9a837dd2e874a4aa4eaddcaa52fb5228aefe43df4ad016a827bc2e7864949cb9
134 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs, many pointing to potentially disposable domains, suggests a phishing or scam lure designed to trick users into downloading further payloads. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it exploits PDF vulnerabilities or uses embedded JavaScript to facilitate malicious downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://loonbedrijfschimmel.nl/userfiles/files/mozukaralupufupu.pdf In PDF document text
    • https://beyondpins.com/calisma2/files/uploads/30590447490.pdfIn PDF document text
    • https://tidurmalam2.com/contents/files/27100823831.pdfIn PDF document text
    • http://lollanaclinic.com/image/upload/File/83995961670.pdfIn PDF document text
    • http://somsit.com/ckfinder/userfiles/files/menovedewutebuwimokiw.pdfIn PDF document text
    • http://numismatika-nbkpdy.cz/userfiles/file/waworufaralalu.pdfIn PDF document text
    • https://www.leasing.net.in/ckfinder/userfiles/files/bawibefebotusewule.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16133b2782edb3---91960314346.pdfIn PDF document text
    • http://builderall.info/userfiles/file/1870537194.pdfIn PDF document text
    • https://pvcmikser.com/upload/files/67421420923.pdfIn PDF document text
    • https://www.tahitotfalu.hu/ckfinder/userfiles/files/minokadexufubuxedifugakef.pdfIn PDF document text
    • https://girilawfirm.com/content_files/files/peloroxetirowadajesuxobu.pdfIn PDF document text
    • http://palenice.net/obrazky_clanky/file/xerekobafadifawivi.pdfIn PDF document text
    • http://zoltysnieg.pl/pliki_wyswig/files/99097589702.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/161354df307a0d---torurobelebej.pdfIn PDF document text
    • https://piphoto.tw/uploads/files/202109080518592207.pdfIn PDF document text
    • https://dbmotorbrokers.com/userfiles/file/titegujavutudak.pdfIn PDF document text
    • https://doublehaircenter.com/upload/ckfinder/files/92488109517.pdfIn PDF document text
    • http://hzkontejnery.cz/ckfinder/userfiles/files/30988489140.pdfIn PDF document text
    • https://theelementrama9.com/userfiles/files/15118254574.pdfIn PDF document text
    • https://lhorizon.ca/uploadHorizon/file/77854622909.pdfIn PDF document text
    • http://narnivet.com/userfiles/files/94544053525.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=1+mb+wala+game+downloadPDF 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_off0000c58d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC58D 10312 bytes
SHA-256: 84ff9d2c63c7eacf3d8d17a2e5e88ef2ca199bfd78ed99f168d65a2cce1f8f86
font_01_sfnt_off0000dc9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC9D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f4af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4AF 17196 bytes
SHA-256: 6d33ac20ea9a1db7f7688bc76e2558b74cc7ad925b489cfce08af38818eaa633