Malicious PDF — malware analysis report

Static analysis result for SHA-256 3af7bb6cf51a7d7c…

MALICIOUS

PDF

92.0 KB Created: 2021-04-14 02:15:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 3c0b886fd91dcc6b849e217ecd243f10 SHA-1: 8635c82012c8a6f552ed84dc2844c13179c9139e SHA-256: 3af7bb6cf51a7d7c8030013609be856865cce3eeb9b5246751080519bba7bb13
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF is flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The presence of numerous external URIs, many pointing to disposable hosting and disguised as legitimate files, suggests a phishing or malware distribution campaign. The document body, though heavily obfuscated, contains references to 'Windows 10 1903 iso 64 bit' and 'wkhtmltopdf', likely serving as a lure to trick users into downloading and opening the malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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.
  • 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://www.mainephilanthropy.org/sites/default/files/ziladiweropisikiforab.pdf In PDF document text
    • https://www.jsif.org/sites/default/files/webform/54250685962.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/fifomibap.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/95941620813.pdfIn PDF document text
    • http://www.friendlycc.com/sites/default/files/webform/74296331991.pdfIn PDF document text
    • https://www.termis.org/system/files/webform/nibobuzokojovafizuza.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/zizepuniket.pdfIn PDF document text
    • http://portal-mysigma.com/system/files/student-proof/wofofokarawivuboniju.pdfIn PDF document text
    • http://www.guninetwork.org/system/files/webform/heirri_proposals/44437875789.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=windows+10+1903+iso++64+bitPDF link annotation
    • https://minorsoncampus.princeton.edu/system/files/webform/45540448673.pdfIn PDF document text
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/kozavexol.pdfIn PDF document text
    • https://gradfutures.princeton.edu/system/files/webform/buviboxakutovovujigobimis.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/26360011081.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/27732669772.pdfIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f367.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF367 5572 bytes
SHA-256: 6138750cf9818d64a3d4cebc9b14ee09ed68b7350c2fa5970ecf18c990b0a04b
font_01_sfnt_off000106ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106EA 5484 bytes
SHA-256: aef103ab41e3da73bab266340d30b2b72198754d3b9805841abdf6b1b7d6b030
font_02_sfnt_off000119b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119B9 18316 bytes
SHA-256: 936c964f6769528e3b26e21caa80d0cded0ac0dd7f40fa587deadf53c523b430
font_03_sfnt_off00014d65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D65 16156 bytes
SHA-256: 1c43a849c929ffe6cc542b081e222ea2e85b3c5078b526d3e17098b8307ec488

Open this report in the interactive analyzer, or submit your own file for analysis.